#!/usr/bin/perl -w 

=head1 NAME

dis2pm.pl - Manakai DOM Perl Module Generator

=head1 SYNOPSIS

  perl dis2pm.pl Foo.dis > Foo.pm

=head1 DESCRIPTION

B<dis2pm> generates a Perl module file (*.pm) that implements
DOM (Document Object Model) interfaces from a "dis" 
(DOM implementation source) file.

This script is part of manakai.

=cut

use strict;
use lib qw<lib ../lib>;
use Message::Markup::SuikaWikiConfig20::Parser;
use Message::Markup::XML::QName qw/DEFAULT_PFX/;
use Message::Util::QName::General [qw/ExpandedURI/], { 
  DOMCore => q<http://suika.fam.cx/~wakaba/archive/2004/8/18/dom-core#>,
  DOMMain => q<http://suika.fam.cx/~wakaba/archive/2004/8/18/dom-core#>,
  infoset => q<http://www.w3.org/2001/04/infoset#>,
  lang => q<http://suika.fam.cx/~wakaba/archive/2004/8/18/lang#>,
  Perl => q<http://suika.fam.cx/~wakaba/archive/2004/8/18/lang#Perl-->,
  license => q<http://suika.fam.cx/~wakaba/archive/2004/8/18/license#>,
  ManakaiDOM => q<http://suika.fam.cx/~wakaba/archive/2004/8/18/manakai-dom#>,
  MDOM_EXCEPTION => q<http://suika.fam.cx/~wakaba/archive/2004/8/4/manakai-dom-exception#>,
  xml => q<http://www.w3.org/XML/1998/namespace>,
  xmlns => q<http://www.w3.org/2000/xmlns/>,
};
my $ManakaiDOMModulePrefix = q<Message::DOM>;
my $MAX_DOM_LEVEL = 3;

my $s;
{
  local $/ = undef;
  $s = <>;
}
my $source = Message::Markup::SuikaWikiConfig20::Parser->parse_text ($s);
my $Info = {};
my $Status = {package => 'main', depth => 0, generated_fragment => 0};
our $result = '';

BEGIN {
  require 'manakai/genlib.pl';
}

sub perl_package_name (%) {
  my %opt = @_;
  my $r;
  if ($opt{if}) {
    $r = $ManakaiDOMModulePrefix . q<::IF::> . perl_name $opt{if};
  } elsif ($opt{iif}) {
    $r = $ManakaiDOMModulePrefix . q<::IIF::> . perl_name $opt{iif};
  } elsif ($opt{name} or $opt{name_with_condition}) {
    if ($opt{name_with_condition}) {
      if ($opt{name_with_condition} =~ /^([^:]+)::([^:]+)$/) {
        $opt{name} = $1;
        $opt{condition} = $2;
      } else {
        $opt{name} = $opt{name_with_condition};
      }
    } 
    $opt{name} = perl_name $opt{name};
    $opt{name} = $opt{prefix} . '::' . $opt{name} if $opt{prefix};
    $r = $ManakaiDOMModulePrefix . q<::> . $opt{name};
  } elsif ($opt{qname} or $opt{qname_with_condition}) {
    if ($opt{qname_with_condition}) {
      if ($opt{qname_with_condition} =~ /^(.+)::([^:]*)$/) {
        $opt{qname} = $1;
        $opt{condition} = $2;
      } else {
        $opt{qname} = $opt{qname_with_condition};
      }
    }
    if ($opt{qname} =~ /^([^:]*):(.*)$/) {
      $opt{ns_prefix} = $1;
      $opt{name} = $2;
    } else {
      $opt{ns_prefix} = DEFAULT_PFX;
      $opt{name} = $opt{qname};
    }
    ## ISSUE: Prefix to ...
    #$r = ns_uri_to_perl_package_name (ns_prefix_to_uri ($opt{ns_prefix})) .
    #     '::' . $opt{name};
    $r = $ManakaiDOMModulePrefix . '::' . $opt{name};
  } elsif ($opt{if_qname} or $opt{if_qname_with_condition}) {
    if ($opt{if_qname_with_condition}) {
      if ($opt{if_qname_with_condition} =~ /^(.+)::([^:]*)$/) {
        $opt{if_qname} = $1;
        $opt{condition} = $2;
      } else {
        $opt{if_qname} = $opt{if_qname_with_condition};
      }
    }
    if ($opt{if_qname} =~ /^([^:]*):(.*)$/) {
      $opt{ns_prefix} = $1;
      $opt{name} = $2;
    } else {
      $opt{ns_prefix} = DEFAULT_PFX;
      $opt{name} = $opt{if_qname};
    }
    ## ISSUE: Prefix to ...
    #$r = ns_uri_to_perl_package_name (ns_prefix_to_uri ($opt{ns_prefix})) .
    #     '::' . $opt{name};
    $r = $ManakaiDOMModulePrefix . '::IF::' . $opt{name};
  } elsif ($opt{full_name}) {
    $r = $opt{full_name};
  } else {
    valid_err q<$opt{name} is false>;
  }
  if ($opt{condition}) {
    $r = $r . '::' . perl_name $opt{condition};
  }
  if ($opt{is_internal}) {
    $r .= '::_internal';
    $r .= '_inherit' if $opt{is_for_inheriting};
  }
  $r;
}

sub perl_package (%) {
  my $fn = perl_package_name @_;
  unless ($fn eq $Status->{package}) {
    $Status->{package} = $fn;
    return perl_statement qq<package $fn>;
  } else {
    return '';
  }
}

sub perl_exception (@) {
  my %opt = @_;
  if ($opt{class} !~ /:/) {
    $opt{class} = perl_package_name name => $opt{class};
  } else {
    $opt{class} = perl_package_name full_name => $opt{class};
  }
  my @param = (-type => $opt{type},
               -object => perl_code_literal ('$self'));
  if (ref $opt{param}) {
    push @param, %{$opt{param}};
  } elsif ($opt{param}) {
    push @param, perl_code_literal ($opt{param});
  }
  if ($opt{subtype} or $opt{subtype_uri}) {
    my $uri = $opt{subtype_uri} || expanded_uri ($opt{subtype});
    push @param, ExpandedURI q<MDOM_EXCEPTION:subtype> => $uri;
  }
  q<report > . $opt{class} . q< > . perl_list @param;
}


{
use re 'eval';
my $RegBlockContent;
$RegBlockContent = qr/(?>[^{}\\]*)(?>(?>[^{}\\]+|\\.|\{(??{$RegBlockContent})\})*)/s;
## Defined by genlib.pl but overridden.
sub perl_code ($;%) {
  my ($s, %opt) = @_;
  valid_err q<Uninitialized value in perl_code>,
    node => $opt{node} unless defined $s;
  $s =~ s[<Q:([^<>]+)>|\b(null|true|false)\b][
    my ($q, $l) = ($1, $2);
    if (defined $q) {
      if ($q =~ /\}/) {
        valid_warn qq<Possible typo in the QName: "$q">;
      }
      perl_literal (expanded_uri ($q));
    } else {
      {true => 1, false => 0, null => 'undef'}->{$l};
    }
  ]ge;
## TODO: Ensure Message::Util::Error imported if try.
## ISSUE: __FILE__ & __LINE__ will break if multiline substition happens.
  $s =~ s{
    \b__([A-Z]+)
    (?:\{($RegBlockContent)\})?
    __\b
  }{
    my ($name, $data) = ($1, $2);
    my $r;
    if ($name eq 'CLASS' or      ## Manakai DOM Class
        $name eq 'SUPER' or      ## Manakai DOM Class (internal)
        $name eq 'IIF' or        ## DOM Interface + Internal interface & prop
        $name eq 'IF') {         ## DOM Interface
      local $Status->{condition} = $Status->{condition};
      if ($data =~ s/::([^:]*)$//) {
        $Status->{condition} = $1;
      }
      $r = perl_package_name {qw/CLASS name SUPER name IIF iif IF if/}->{$name}
                                         => $data,
                             is_internal => {qw/SUPER 1/}->{$name},
                             condition => $Status->{condition};
    } elsif ($name eq 'INT') {    ## Internal Method / Attr Name
      if (defined $data) {
        if ($data =~ /^{($RegBlockContent)}$/o) {
          $data = $1;
          my $name = $1 if $data =~ s/^\s*(\w+)\s*(?:$|:\s*)// or
            valid_err qq<Syntax of preprocessing macro "INT" is invalid>,
            node => $opt{node};
          local $Status->{preprocess_variable}
                           = {%{$Status->{preprocess_variable}||{}}};
          while ($data =~ /\G(\S+)\s*(?:=>\s*(\S+)\s*)?(?:,\s*|$)/g) {
            my ($n, $v) = ($1, defined $2 ? $2 : 1);
            for ($n, $v) {
              s/^'([^']+)'$/$1/; ## ISSUE: Doesn't support quoted-'
            }
            $Status->{preprocess_variable}->{$n} = $v;
          }
          valid_err q<Preprocessing macro INT{} cannot be used here>
            unless $opt{internal};
          $r = perl_comment ("INT: $name").
               $opt{internal}->($name);
        } elsif ($data =~ s/^SP://) {
          $r = '___'.$data;
        } else {
          $r = perl_internal_name $data;
        }
      } else {
        valid_err q<Preprocessing macro INT cannot be used here>
          unless $opt{internal};
        $r = $opt{internal}->();
      }
    } elsif ($name eq 'DEEP') {   ## Deep Method Call
      $r = 'do { local $Error::Depth = $Error::Depth + 1;' . perl_code ($data) .
           '}';
    } elsif ($name eq 'EXCEPTION' or $name eq 'WARNING') {
                                  ## Raising an Exception or Warning
      if ($data =~ s/^\s*(\w+)\s*\.\s*(\w+)\s*(?:\.\s*([\w:]+)\s*)?(?:::\s*|$)//) {
        $r = perl_exception (level => $name,
                             class => $1,
                             type => $2,
                             subtype => $3,
                             param => perl_code $data);
      } else {
        valid_err qq<Exception type and name required: "$data">,
          node => $opt{node};
      }      
    } elsif ($name eq 'CODE') { # Built-in code
      my ($nm, %param);
      if ($data =~ s/^(\w+)\s*(?::\s*|$)//) {
        $nm = $1;
      } elsif ($data =~ s/^<([^<>]+)>\s*(?::\s*|$)//) {
        $nm = $1;
      } else {
        valid_err q<Built-in code name required>;
      }
      while ($data =~ /\G(\S+)\s*=>\s*(\S+)\s*(?:,\s*|$)/g) {
        $param{$1} = $2;
      }
      $r = perl_builtin_code ($nm, condition => $opt{condition}, %param);
    } elsif ($name eq 'PACKAGE' and $data) {
      if ($data eq 'Global') {
        $r = $ManakaiDOMModulePrefix;
      } else {
        valid_err qq<PACKAGE "$data" not supported>;
      }
    } elsif ($name eq 'REQUIRE') {
      $r = perl_statement (q<require >. perl_package_name name => $data);
    } elsif ($name eq 'WHEN') {
      if ($data =~ s/^\s*IS\s*\{($RegBlockContent)\}::\s*//o) {
        my $v = $1;
        if ($v =~ /^\s*'([^']+)'\s*$/) { ## ISSUE: Doesn't support quoted-'
          if ($Status->{preprocess_variable}->{$1}) {
            $r = perl_code ($data, %opt);
          } else {
            $r = perl_comment ($data);
          }
        } else {
          valid_err qq<WHEN-IS condition "$v" is invalid>,
            node => $opt{node};
        }
      } else {
        valid_err qq<Syntax for preprocessing macro "WHEN" is invalid>,
          node => $opt{node};
      }
    } elsif ($name eq 'FILE' or $name eq 'LINE' or $name eq 'PACKAGE') {
      $r = qq<__${name}__>;
    } else {
      valid_err qq<Preprocessing macro "$name" not supported>;
    }
    $r;
  }goex;
  $s;
}
}

## Defined in genlib.pl but overridden.
sub perl_code_source ($%) {
  my ($s, %opt) = @_;
  sprintf qq<\n#line %d "File <%s> Node <%s>"\n%s\n> .
          qq<#line 1 "File <%s> Chunk #%d"\n>,
    $opt{line} || 1, $opt{file} || $Info->{source_filename},
    $opt{path} || 'x:unknown ()', $s, 
    $opt{file} || $Info->{source_filename}, ++$Status->{generated_fragment};
}

sub perl_builtin_code ($;%);
sub perl_builtin_code ($;%) {
  my ($name, %opt) = @_;
  $opt{condition} ||= $Status->{condition};
  my $r;
  if ($name eq 'DOMString') {
    $name = $1 if $name =~ /(\w+)$/;
    $r = q{
          if (defined $arg) {
            if (ref $arg) {
              if (ref $arg eq 'SCALAR') {
                $r = bless {value => $$arg}, $self;
              } elsif ($arg->isa ('IF')) {
                $r = $arg;
              } else {
                $r = bless {value => ''.$arg}, $self;
              }
            } else {
              $r = bless {value => $arg}, $self;
            }
          } else {
            $r = undef; # null
          }
    };
    $r =~ s/'IF'/perl_literal (perl_package_name (if => $name))/ge;
    $r =~ s/\$self\b/perl_literal (perl_package_name (name => $name))/ge; 
    $opt{s} or valid_err q<Built-in code parameter "s" required>;
    $r =~ s/\$arg\b/\$$opt{s}/g;
    $opt{r} or valid_err q<Built-in code parameter "r" required>;
    $r =~ s/\$r\b/\$$opt{r}/g;
    $r =~ s/\$$opt{r} = \$$opt{s};/#/g if $opt{r} eq $opt{s}; 
  } elsif (type_isa ($name, ExpandedURI q<ManakaiDOM:ManakaiDOMNamespaceURI>)) {
    $r = perl_statement perl_exception
                (level => 'WARNING',
                 class => 'ManakaiDOMImplementationWarning',
                 type => 'MDOM_NS_EMPTY_URI',
                 param => {
                   ExpandedURI q<MDOM_EXCEPTION:param-name> => $opt{s},
                 });
    if ($opt{condition} and $opt{condition} ne 'DOM2') {
      $r .= perl_statement q<$out = undef>;
    }
    $r = perl_if (q<defined $in and $in eq ''>, $r);
    $opt{s} or valid_err q<Built-in code parameter "s" required>;
    $r =~ s/\$in\b/\$$opt{s}/g;
    $opt{r} or valid_err q<Built-in code parameter "r" required>;
    $r =~ s/\$out\b/\$$opt{r}/g;
  } elsif ($name eq 'UniqueID') {
    $r = q{(
      sprintf 'mid:%d.%d.%s.dom.manakai@suika.fam.cx',
              time, $$,
              ['A'..'Z', 'a'..'z', '0'..'9']->[rand 62] .
              ['A'..'Z', 'a'..'z', '0'..'9']->[rand 62] .
              ['A'..'Z', 'a'..'z', '0'..'9']->[rand 62] .
              ['A'..'Z', 'a'..'z', '0'..'9']->[rand 62] .
              ['A'..'Z', 'a'..'z', '0'..'9']->[rand 62]
    )};
## TODO: Check as HTML Name if not XML.
  } elsif ($name eq 'CheckQName') {
    $opt{version} = '1.0' if $opt{condition} and $opt{condition} eq 'DOM2';
    my $chk = perl_if
                (qq<##CHKNAME##>, undef,
                  (perl_statement
                    perl_exception 
                      (class => 'DOMException',
                       type => 'INVALID_CHARACTER_ERR',
                       subtype_uri =>
                         ExpandedURI q<MDOM_EXCEPTION:MDOM_BAD_NAME>,
                       param => {
                         ExpandedURI q<DOMCore:name>
                             => perl_code_literal
                                  (perl_var type => '$', local_name => 'qname'),
                       }))) .
              perl_if
                (qq<##CHKQNAME##>, undef,
                  (perl_statement
                    perl_exception
                      (class => 'DOMException',
                       type => 'NAMESPACE_ERR',
                       subtype_uri =>
                         ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_MALFORMED_QNAME>,
                       param => {
                         ExpandedURI q<DOMCore:qualifiedName>
                             => perl_code_literal
                                  (perl_var type => '$', local_name => 'qname'),
                       })));
    my $chk10 = $chk;
    $chk10 =~ s{##CHKNAME##}
               {q<$qname =~ /\A\p{InXML_NameStartChar10}>.
                q<\p{InXMLNameChar10}*\z/>}ge;
    $chk10 =~ s{##CHKQNAME##}
               {q<$qname =~ /\A\p{InXML_NCNameStartChar10}>.
                q<\p{InXMLNCNameChar10}*>.
                q<(?::\p{InXML_NCNameStartChar10}>.
                q<\p{InXMLNCNameChar10}*)?\z/>}ge;
    my $chk11 = $chk;
    $chk11 =~ s{##CHKNAME##}
               {q<$qname =~ /\A\p{InXMLNameStartChar11}>.
                q<\p{InXMLNameChar11}*\z/>}ge;
    $chk11 =~ s{##CHKQNAME##}
               {q<$qname =~ /\A\p{InXMLNCNameStartChar11}>.
                q<\p{InXMLNCNameChar11}*>.
                q<(?::\p{InXMLNCNameStartChar11}>.
                q<\p{InXMLNCNameChar11}*)?\z/>}ge;
    my %class;
    if ($opt{version} and $opt{version} eq '1.0') {
      $r = $chk10;
      %class = (qw/InXML_NameStartChar10 InXMLNameChar10
                   InXML_NCNameStartChar10 InXMLNCNameChar10/);
    } elsif ($opt{version} and $opt{version} eq '1.1') {
      $r = $chk11;
      %class = (qw/InXMLNameStartChar11 InXMLNameChar11
                   InXMLNCNameStartChar11 InXMLNCNameChar11/);
    } elsif ($opt{version}) {
      $r = perl_if (q<defined >.
                    perl_var (type => '$', local_name => $opt{version}) .
                    q< and >.
                    perl_var (type => '$', local_name => $opt{version}) .
                    q< eq '1.1'>, $chk11, $chk10);
      %class = (qw/InXML_NameStartChar10 InXMLNameChar10
                   InXML_NCNameStartChar10 InXMLNCNameChar10
                   InXMLNameStartChar11 InXMLNameChar11
                   InXMLNCNameStartChar11 InXMLNCNameChar11/);
    } else {
      valid_err q<Built-in code parameter "version" required>;
    }
    $opt{qname} or valid_err q<Built-in code parameter "qname" required>;
    $r =~ s/\$qname\b/\$$opt{qname}/g;
    $Info->{Require_perl_package_use}->{'Char::Class::XML'} or
      valid_err q<"Char::Class::XML" must be "Require"d in the interface >.
                qq{"$Status->{IF}", condition "$Status->{condition}"};
    for (%class) {
      $Info->{Require_perl_package_use}->{'Char::Class::XML::::Import'}->{$_} or
        valid_err qq<"$_" must be exported from "Char::Class::XML" in the >.
                  qq{interface "$Status->{IF}", condition }.
                  qq{"$Status->{condition}"};
    }
  } elsif ($name eq 'CheckNCName') {
    $opt{version} = '1.0' if $opt{condition} and $opt{condition} eq 'DOM2';
    my $chk = perl_if
                (qq<##CHKNAME##>, undef,
                  (perl_statement
                    perl_exception 
                      (class => 'DOMException',
                       type => 'INVALID_CHARACTER_ERR',
                       subtype_uri =>
                         ExpandedURI q<MDOM_EXCEPTION:MDOM_BAD_NAME>,
                       param => {
                         ExpandedURI q<DOMCore:name>
                             => perl_code_literal
                                  (perl_var type => '$', local_name => 'qname'),
                       }))) .
              perl_if
                (qq<##CHKNCNAME##>, undef,
                  (perl_statement
                    perl_exception
                      (class => 'DOMException',
                       type => 'NAMESPACE_ERR',
                       subtype_uri =>
                         ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_BAD_NCNAME>,
                       param => {
                         ExpandedURI q<infoset:name>
                             => perl_code_literal
                                  (perl_var type => '$', local_name => 'qname'),
                       })));
    my $chk10 = $chk;
    $chk10 =~ s{##CHKNAME##}
               {q<$qname =~ /\A\p{InXML_NameStartChar10}>.
                q<\p{InXMLNameChar10}*\z/>}ge;
    $chk10 =~ s{##CHKNCNAME##}
               {q<$qname =~ /:/>}ge;
    my $chk11 = $chk;
    $chk11 =~ s{##CHKNAME##}
               {q<$qname =~ /\A\p{InXMLNameStartChar11}>.
                q<\p{InXMLNameChar11}*\z/>}ge;
    $chk11 =~ s{##CHKNCNAME##}
               {q<$qname =~ /:/>}ge;
    my $t = ($opt{empty} and $opt{empty} eq 'warn3' and
             (not $opt{condition} or $opt{condition} ne 'DOM2')) ?
            perl_if 
              (q<defined $qname and $qname eq q<>>,
               perl_statement (perl_exception
                 (level => 'WARNING',
                  class => 'ManakaiDOMImplementationWarning',
                  type => 'MDOM_NS_EMPTY_PREFIX',
                  param => {
                    ExpandedURI q<MDOM_EXCEPTION:param-name> => $opt{ncname},
                  })).
               perl_statement (q<$qname = undef>)) : '';
    my %class;
    if ($opt{version} and $opt{version} eq '1.0') {
      $r = $chk10;
      %class = (qw/InXML_NameStartChar10 InXMLNameChar10/);
    } elsif ($opt{version} and $opt{version} eq '1.1') {
      $r = $chk11;
      %class = (qw/InXMLNameStartChar11 InXMLNameChar11/);
    } elsif ($opt{version}) {
      $r = perl_if (q<defined >.
                    perl_var (type => '$', local_name => $opt{version}) .
                    q< and >.
                    perl_var (type => '$', local_name => $opt{version}) .
                    q< eq '1.1'>, $chk11, $chk10);
      %class = (qw/InXML_NameStartChar10 InXMLNameChar10
                   InXMLNameStartChar11 InXMLNameChar11/);
    } else {
      valid_err q<Built-in code parameter "version" required>;
    }
    $r = $t . $r;
    $opt{ncname} or valid_err q<Built-in code parameter "ncname" required>;
    $r =~ s/\$qname\b/\$$opt{ncname}/g;
    $Info->{Require_perl_package_use}->{'Char::Class::XML'} or
      valid_err q<"Char::Class::XML" must be "Require"d in the interface >.
                qq{"$Status->{IF}", condition "$Status->{condition}"};
    for (%class) {
      $Info->{Require_perl_package_use}->{'Char::Class::XML::::Import'}->{$_} or
        valid_err qq<"$_" must be exported from "Char::Class::XML" in the >.
                  qq{interface "$Status->{IF}", condition }.
                  qq{"$Status->{condition}"};
    }
  } elsif ($name eq 'CheckName') {
    $opt{version} = '1.0' if $opt{condition} and 
                             ($opt{condition} eq 'DOM2' or
                              $opt{condition} eq 'DOM1');
    my $chk = perl_if
                (qq<##CHKNAME##>, undef,
                  (perl_statement
                    perl_exception 
                      (class => 'DOMException',
                       type => 'INVALID_CHARACTER_ERR',
                       subtype_uri =>
                         ExpandedURI q<MDOM_EXCEPTION:MDOM_BAD_NAME>,
                       param => {
                         ExpandedURI q<DOMCore:name>
                             => perl_code_literal
                                  (perl_var type => '$', local_name => 'qname'),
                       })));
    my $chk10 = $chk;
    $chk10 =~ s{##CHKNAME##}
               {q<$qname =~ /\A\p{InXML_NameStartChar10}>.
                q<\p{InXMLNameChar10}*\z/>}ge;
    my $chk11 = $chk;
    $chk11 =~ s{##CHKNAME##}
               {q<$qname =~ /\A\p{InXMLNameStartChar11}>.
                q<\p{InXMLNameChar11}*\z/>}ge;
    my %class;

    if ($opt{version} and $opt{version} eq '1.0') {
      $r = $chk10;
      %class = (qw/InXML_NameStartChar10 InXMLNameChar10/);
    } elsif ($opt{version} and $opt{version} eq '1.1') {
      $r = $chk11;
      %class = (qw/InXMLNameStartChar11 InXMLNameChar11/);
    } elsif ($opt{version}) {
      $r = perl_if (q<defined >.
                    perl_var (type => '$', local_name => $opt{version}) .
                    q< and >.
                    perl_var (type => '$', local_name => $opt{version}) .
                    q< eq '1.1'>, $chk11, $chk10);
      %class = (qw/InXML_NameStartChar10 InXMLNameChar10
                   InXMLNameStartChar11 InXMLNameChar11/);
    } else {
      valid_err q<Built-in code parameter "version" required>;
    }
    $opt{name} or valid_err q<Built-in code parameter "name" required>;
    $r =~ s/\$qname\b/\$$opt{name}/g;
    $Info->{Require_perl_package_use}->{'Char::Class::XML'} or
      valid_err q<"Char::Class::XML" must be "Require"d in the interface >.
                qq{"$Status->{IF}", condition "$Status->{condition}"};
    for (%class) {
      $Info->{Require_perl_package_use}->{'Char::Class::XML::::Import'}->{$_} or
        valid_err qq<"$_" must be exported from "Char::Class::XML" in the >.
                  qq{interface "$Status->{IF}", condition }.
                  qq{"$Status->{condition}"};
    }
  } elsif ($name eq 'CheckNull') {
    $r = perl_code q{
      __EXCEPTION{
        ManakaiDOMImplementationException.PARAM_NULL_POINTER::
          <Q:MDOM_EXCEPTION:param-name> => 'arg',
      }__ unless defined $arg;
    };
    $opt{s} or valid_err q<Built-in code parameter "s" required>;
    $r =~ s/\$arg\b/\$$opt{s}/g;
    $r =~ s/'arg'/perl_literal ($opt{s})/ge;
  } elsif ($name eq 'XMLVersion') {
    $r = perl_code q{
          $r = defined $node->{<Q:DOMCore:hasFeature>}->{XML} ?
                 defined $node->{<Q:infoset:version>} ?
                   $node->{<Q:infoset:version>} : '1.0' : null;
          };
    $opt{docNode} or valid_err q<Built-in code parameter "docNode" required>;
    $r =~ s/\$node\b/\$$opt{docNode}/g;
    $opt{out} or valid_err q<Built-in code parameter "out" required>;
    $r =~ s/\$r\b/\$$opt{out}/g;
  } elsif ($name eq 'XMLNS') {
    for (qw/docNode namespaceURI qualifiedName out-version
            out-prefix out-localName/) {
      $opt{$_} or valid_err qq<Built-in code parameter "$_" required>,
                    node => $opt{node};
    }

    ## Check the Document XML version
    ## - The Document must support the "XML" feature
    $r = perl_builtin_code ('XMLVersion', %opt,
                            out => $opt{'out-version'},
                            docNode => $opt{docNode});
    $r .= perl_if
           (q<defined >.perl_var (type => '$',
                                  local_name => $opt{'out-version'}),
            undef,
            perl_statement
              perl_exception
                (type => 'NOT_SUPPORTED_ERR',
                 class => 'DOMException',
                 subtype_uri =>
                   ExpandedURI q<MDOM_EXCEPTION:MDOM_DOC_NOSUPPORT_XML>));

    ## Check the QName
    $r .= perl_builtin_code ('CheckQName', %opt,
                             qname => $opt{qualifiedName},
                             version => $opt{'out-version'});

    ## Split QName into prefix and local name
    my $prefix = perl_var (type => '$', local_name => $opt{'out-prefix'});
    my $lname = perl_var (type => '$', local_name => $opt{'out-localName'});
    my $nsURI = perl_var (type => '$', local_name => $opt{namespaceURI});
    $r .= qq{($prefix, $lname) = split /:/, \$$opt{qualifiedName}, 2;
             ($prefix, $lname) = (undef, $prefix) unless defined $lname;};

    ## Check namespace binding
    $r .= perl_if
           (qq<defined $prefix>,
            perl_cases (
              qq<not defined $nsURI>,
                => perl_statement
                     (perl_exception
                        (type => 'NAMESPACE_ERR',
                         class => 'DOMException',
                         subtype_uri =>
                   ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_PREFIX_WITH_NULL_URI>,
                         param => {
                           ExpandedURI q<infoset:prefix> =>
                                           perl_code_literal ($prefix),
                         })),
              qq<$prefix eq 'xml' and $nsURI ne >.
              perl_literal (ExpandedURI q<xml:>)
                => perl_statement
                     (perl_exception
                        (type => 'NAMESPACE_ERR',
                         class => 'DOMException',
                         subtype_uri =>
                   ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_XML_WITH_OTHER_URI>,
                         param => {
                           ExpandedURI q<infoset:namespaceName> =>
                                           perl_code_literal ($nsURI),
                         })),
              qq<$prefix eq 'xmlns' and $nsURI ne >.
              perl_literal (ExpandedURI q<xmlns:>)
                => perl_statement
                     (perl_exception
                        (type => 'NAMESPACE_ERR',
                         class => 'DOMException',
                         subtype_uri =>
                   ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_XMLNS_WITH_OTHER_URI>,
                         param => {
                           ExpandedURI q<infoset:namespaceName> =>
                                           perl_code_literal ($nsURI),
                         })),
              perl_literal (ExpandedURI q<xml:>).
              qq< eq $nsURI and $prefix ne 'xml'>
                => perl_statement
                     (perl_exception
                        (type => 'NAMESPACE_ERR',
                         class => 'DOMException',
                         subtype_uri =>
                   ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_OTHER_WITH_XML_URI>,
                         param => {
                           ExpandedURI q<infoset:prefix> =>
                                           perl_code_literal ($prefix),
                           ExpandedURI q<DOMCore:qualifiedName>
                             => perl_code_literal ('$qualifiedName'),
                         })),
              perl_literal (ExpandedURI q<xmlns:>).
              qq< eq $nsURI and $prefix ne 'xmlns'>
                => perl_statement
                     (perl_exception
                        (type => 'NAMESPACE_ERR',
                         class => 'DOMException',
                         subtype_uri =>
                   ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_OTHER_WITH_XMLNS_URI>,
                         param => {
                           ExpandedURI q<infoset:prefix> =>
                                           perl_code_literal ($prefix),
                           ExpandedURI q<DOMCore:qualifiedName>
                             => perl_code_literal ('$qualifiedName'),
                         })),
              perl_literal (ExpandedURI q<xmlns:>).
              qq< eq $nsURI and $prefix eq 'xmlns' and $lname eq 'xmlns'>
                => perl_statement
                     (perl_exception
                        (type => 'NAMESPACE_ERR',
                         class => 'DOMException',
                         subtype_uri =>
                           ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_XMLNS_XMLNS>,
                         param => {
                         })),
            ),
            perl_cases ( # No prefix
              perl_literal (ExpandedURI q<xml:>).qq< eq $nsURI>
                => perl_statement
                     (perl_exception
                        (type => 'NAMESPACE_ERR',
                         class => 'DOMException',
                         subtype_uri =>
                   ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_OTHER_WITH_XML_URI>,
                         param => {
                           ExpandedURI q<DOMCore:qualifiedName>
                             => perl_code_literal ($lname),
                         })),
              perl_literal (ExpandedURI q<xmlns:>).
              qq< eq $nsURI and $lname ne 'xmlns'>
                => perl_statement
                     (perl_exception
                        (type => 'NAMESPACE_ERR',
                         class => 'DOMException',
                         subtype_uri =>
                   ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_OTHER_WITH_XMLNS_URI>,
                         param => {
                           ExpandedURI q<DOMCore:qualifiedName>
                             => perl_code_literal ($lname),
                         })),
              qq<$lname eq 'xmlns' and $nsURI ne >.
              perl_literal (ExpandedURI q<xmlns:>)
                => perl_statement
                     (perl_exception
                        (type => 'NAMESPACE_ERR',
                         class => 'DOMException',
                         subtype_uri =>
                   ExpandedURI q<MDOM_EXCEPTION:MDOM_NS_XMLNSQ_WITH_OTHER_URI>,
                         param => {
                           ExpandedURI q<infoset:namespaceName>
                             => perl_code_literal ($nsURI),
                         })),
            ));
  } elsif ($name eq 'isRelativeDOMURI') {
    $r = q<$in !~ /^[0-9A-Za-z+_.%-]:/>;
    ## TODO: I18n consideration
    for (qw/in/) {
      $opt{$_} or valid_err qq<Built-in code parameter "$_" required>,
                    node => $opt{node};
      $r =~ s/\$$_/\$$opt{$_}/g;
    }
  } elsif ($name eq 'ParseFeatures') {
    $r = q{
      {
        if (ref $in eq 'HASH') {
          for (keys %$in) {
            if ($_ =~ /^\+(.+)/) {
              $out{lc $1} = {version => $in{$_}, plus => 1};
            } else {
              $out{lc $_} = {version => $in{$_}, plus => 0};
            }
          }
        } else {
          my @f = grep {length} split /\s+/, $in;
          for (my $i = 0; $i < @f; $i++) {
            my ($name, $plus) = (lc $f[$i]);
            $plus = 1 if $name =~ s/^\+//;
            if ($i + 1 < @f and $f[$i + 1] =~ /^\d/) {
              $out{$name} = {version => $f[$i + 1], plus => $plus}; $i++;
            } else {
              $out{$name} = {version => undef, plus => $plus};
            }
          }
        }
      }
    };           ## NOTE: Feature name is case-insensitive.
    ## NOTE: This code does not work if a feature appears more than
    ##       one versions.  DOM specification does not specify how 
    ##       implementations should cope with such case.
    for (qw/in out/) {
      $opt{$_} or valid_err qq<Built-in code parameter "$_" required>,
                    node => $opt{node};
      $r =~ s/\$$_/\$$opt{$_}/g;
      $r =~ s/%$_/%$opt{$_}/g;
    }
  } else {
    valid_err qq<Built-in code "$name" not defined>;
  }
  $r;
}

sub ops2perl () {
  my $result = '';
  for (keys %{$Status->{Operator}}) {
    if ($_ eq 'DESTROY') {
      $result .= perl_statement q<sub DESTROY ($)>;
      $result .= perl_statement
                 perl_assign
                      perl_var (type => '*', local_name => 'DESTROY')
                   => $Status->{Operator}->{DESTROY};
      delete $Status->{Operator}->{DESTROY};
    } elsif ($_ eq 'new') {
      $result .= perl_statement q<sub new ($)>;
      $result .= perl_statement
                 perl_assign
                      perl_var (type => '*', local_name => 'new')
                   => $Status->{Operator}->{$_};
      delete $Status->{Operator}->{$_};
    } elsif ($_ eq 'object-error-handler') {
      $result .= perl_statement q<sub ___report_error ($$)>;
      $result .= perl_statement
                 perl_assign
                      perl_var (type => '*', local_name => '___report_error')
                   => $Status->{Operator}->{$_};
      delete $Status->{Operator}->{$_};
    } elsif ({qw[
                  +  1 -  1 *  1 /  1 %  1 **  1 <<  1 >>  1 x  1 .  1
                  += 1 -= 1 *= 1 /= 1 %= 1 **= 1 <<= 1 >>= 1 x= 1 .= 1
                  <  1 <= 1 >  1 >= 1 == 1 != 1 <=> 1
                  lt 1 le 1 gt 1 ge 1 eq 1 ne 1 cmp 1
                  & 1 | 1 ^ 1
                  neg 1 ! 1 ~ 1
                  ++ 1 -- 1
                  atan2 1 cos 1 sin 1 exp 1 abs 1 log 1 sqrt 1
                  bool 1 "" 1 0+ 1
                  <> 1
                  ${} 1 @{} 1 %{} 1 &{} 1 *{} 1
                ]}->{$_}) {
      # 
    } else {
      valid_err qq[$Status->{if}: Operator "$_" not supported];
    }
  }
  if (keys %{$Status->{Operator}}) {
    $result .= perl_statement 'use overload ' .
                   perl_list map ({($_,
                                   perl_code_literal $Status->{Operator}->{$_})}
                                  keys %{$Status->{Operator}}),
                             fallback => 1;
  }
  $result;
}



sub qname_label ($;%) {
  my ($node, %opt) = @_;
  my $q = defined $opt{qname} ? $opt{qname}
                              : $node->get_attribute_value ('QName');
  my $prefix = DEFAULT_PFX;
  if ($q =~ s/^([^:]*)://) {
    $prefix = $1;
  }

  if ($prefix ne DEFAULT_PFX or not $opt{no_default_ns}) {
      if (defined $Info->{Namespace}->{$prefix}) {
        my $uri = $Info->{Namespace}->{$prefix};
        if (defined $Status->{ns_in_doc}->{$prefix}) {
          if ($Status->{ns_in_doc}->{$prefix} ne $uri) {
            my $i = 1;
            {
              if (defined $Status->{ns_in_doc}->{$prefix.$i}) {
                if ($Status->{ns_in_doc}->{$prefix.$i} eq $uri) {
                  $prefix .= $i; last;
                } else {
                  $i++; redo;
                }
              } else {
                $Status->{ns_in_doc}->{$prefix.$i} = $uri;
                $prefix .= $i; last;
              }
            }
          }
        } else {
          $Status->{ns_in_doc}->{$prefix} = $uri;
        }
      } else {
        valid_err q<Namespace prefix "$prefix" not defined>,
          node => $node->get_attribute ('QName');
      } 
  }

  $opt{out_type} ||= ExpandedURI q<DOMMain:any>;
  if ($opt{out_type} eq ExpandedURI q<lang:pod>) {
    pod_code ($prefix eq DEFAULT_PFX ? $q : qq<$prefix:$q>);
  } else {
    $prefix eq DEFAULT_PFX ? qq<"$q"> : qq<"$prefix:$q">;
  }
}

{
my $nest = 0;
sub type_normalize ($);
sub type_normalize ($) {
  my ($uri) = @_;
  $nest++ == 100 and valid_err q<Possible loop for DataTypeAlias of <$uri>>;
  if ($Info->{DataTypeAlias}->{$uri}->{canon_uri}) {
    $uri = type_normalize ($Info->{DataTypeAlias}->{$uri}->{canon_uri});
  }
  $nest--;
  $uri;
}
}

{
my $nest = 0;
sub type_isa ($$);
sub type_isa ($$) {
  my ($uri, $uri2) = @_;
  $nest++ == 100 and valid_err qq<Possible loop for <DataType/ISA> of <$uri>>;
  my $r = 0;
  if ($uri eq $uri2) {
    $r = 1;
  } else {
    for (@{$Info->{DataTypeAlias}->{$uri}->{isa_uri}||[]}) {
      if (type_isa $_, $uri2) {
        $r = 1;
        last;
      }
    }
  }
  $nest--;
  $r;
}
}

sub type_label ($;%) {
  my $uri = type_normalize shift;
  my %opt = @_;
  my $pod_code = sub { $opt{is_pod} ? pod_code $_[0] : $_[0] };
  my $r = {
    ExpandedURI q<DOMMain:unsigned-long> => q<Unsigned Long Integer>,
    ExpandedURI q<DOMMain:unsigned-short> => q<Unsigned Short Integer>,
    ExpandedURI q<ManakaiDOM:ManakaiDOMURI>
      => $pod_code->(q<DOMString>).q< (DOM URI)>,
    ExpandedURI q<ManakaiDOM:ManakaiDOMNamespaceURI>
      => $pod_code->(q<DOMString>).q< (Namespace URI)>,
    ExpandedURI q<ManakaiDOM:ManakaiDOMFeatureName>
      => $pod_code->(q<DOMString>).q< (DOM Feature name)>,
    ExpandedURI q<ManakaiDOM:ManakaiDOMFeatureVersion>
      => $pod_code->(q<DOMString>).q< (DOM Feature version)>,
    ExpandedURI q<ManakaiDOM:ManakaiDOMFeatures>
      => $pod_code->(q<DOMString>).q< (DOM features)>,
  }->{$uri};
  unless ($r) {
    if ($uri =~ /([\w_-]+)$/) {
      my $label = $1;
      $label =~ s/--+/ /g;
      $label =~ s/__+/ /g;
      $r = $pod_code->($label);
    } else {
      $r = $pod_code->("<$uri>");
    }
  }
  $r;
}

sub type_package_name ($) {
  my $qname = shift;
  if ($qname =~ /^([^:]*):([^:]*)$/) {
    perl_package_name name => perl_name $2, ucfirst => 1;
  } else {
    perl_package_name name => perl_name $qname, ucfirst => 1;
  }
}

sub ns_uri_to_perl_package_name ($) {
  my $uri = shift;
  if ($Info->{uri_to_perl_package}->{$uri}) {
    return $Info->{uri_to_perl_package}->{$uri};
  } else {
    return qq<Perl package name for namespace <$uri> not defined>;
  }
}

sub ns_prefix_to_uri ($) {
  my $pfx = shift;
  if (exists $Info->{Namespace}->{$pfx}) {
    if (not defined $Info->{Namespace}->{$pfx}) {
      valid_err qq<Namespace name for "$pfx" not defined>;
    } else {
      return $Info->{Namespace}->{$pfx};
    }
  } else {
    valid_err qq<Namespace prefix "$pfx" not declared>;
  }  
}

sub type_expanded_uri ($) {
  my $qname = shift || '';
  if ($qname =~ /^[a-z-]+$/ or $qname eq 'Object') {
    expanded_uri ("DOMMain:$qname");
  } else {
    expanded_uri ($qname);
  }
}

sub expanded_uri ($) {
  my $lname = shift || '';
  my $pfx = DEFAULT_PFX;
  if ($lname =~ s/^([^:]*)://) {
    $pfx = $1;
  }
  ns_prefix_to_uri ($pfx) . $lname;
}

sub array_contains ($$) {
  my ($array, $val) = @_;
  if (ref $array eq 'ARRAY') {
    for (@$array) {
      return 1 if $_ eq $val;
    }
  } else {
    return $array eq $val;
  }
  return 0;
}


sub get_warning_perl_code ($) {
  my $pnode = shift;
  my $r = '';
  for my $node (@{$pnode->child_nodes}) {
    next unless $node->node_type eq '#element' and
                $node->local_name eq 'Warning';
    my %param;
    for (@{$node->child_nodes}) {
      next unless $_->node_type eq '#element' and
                  $_->local_name eq 'Param';
      $param{expanded_uri $_->get_attribute_value ('QName')}
        = perl_code_literal get_value_literal ($_, name => 'Value',
                                               type_name => 'Type');
    }
    $r .= perl_statement 
              perl_exception
                class => type_package_name $node->get_attribute_value
                                                    ('Type',
                                                     default => 'DOMMain:any'),
                type => $node->get_attribute_value ('Name'),
                param => \%param;
  }
  $r;
} # get_warning_perl_code

sub get_perl_definition_node ($%) {
  my ($node, %opt) = @_;
  my $ln = $opt{name} || 'Def';
  my $def = $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->local_name eq $ln and
    type_expanded_uri $you->get_attribute_value ('Type', default => '')
      eq ExpandedURI q<lang:Perl> and
    condition_match ($you, %opt);
  }) || ($opt{use_dis} and $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->local_name eq $ln and
    $you->get_attribute_value ('Type', default => '')
      eq ExpandedURI q<lang:dis> and
    condition_match ($you, %opt);
  })) || $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->local_name eq $ln and
    not $you->get_attribute_value ('Type', default => '') and
    condition_match ($you, %opt);
  }) || $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->local_name eq $ln and
    type_expanded_uri $you->get_attribute_value ('Type', default => '')
      eq ExpandedURI q<lang:Perl> and
    condition_match ($you); # no condition specified
  }) || ($opt{use_dis} and $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->local_name eq $ln and
    type_expanded_uri $you->get_attribute_value ('Type', default => '')
      eq ExpandedURI q<lang:dis> and
    condition_match ($you); # no condition specified
  })) || $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->local_name eq $ln and
    not $you->get_attribute_value ('Type', default => '') and
    condition_match ($you); # no condition specified
  });
  $def;
}

sub get_perl_definition ($%) {
  my ($node, %opt) = @_;
  my $def = get_perl_definition_node $node, %opt;
  $def ? $def->value : $opt{default};
}

sub dis2perl ($) {
  my $node = shift;
  my $r = '';
  for (@{$node->child_nodes}) {
    next unless $_->node_type eq '#element';
    if ($_->local_name eq 'GetProp') {
      $r .= perl_statement perl_assign
              perl_var (type => '$', local_name => 'r')
              => '$self->{node}->{' .
                 perl_literal (expanded_uri ($_->value)) . '}';
    } elsif ($_->local_name eq 'GetPropNode') {
      $r .= perl_statement perl_assign
              perl_var (type => '$', local_name => 'r')
              => '$self->{node}->{' .
                 perl_literal (expanded_uri ($_->value)) . '}';
                             ## Conditional
      $r .= perl_statement
              perl_code q{$r = __CLASS{Node}__->__INT{getNodeReference}__ ($r)
                          if defined $r};
    } elsif ($_->local_name eq 'SetProp') {
      my $t = perl_statement perl_assign
              '$self->{node}->{' .
                 perl_literal (expanded_uri ($_->value)) . '}'
              => perl_var (type => '$', local_name => 'given');
      if ($_->get_attribute_value ('CheckReadOnly', default => 1)) {
        $r .= perl_if
                q[$self->{'node'}->{].
                  perl_literal (ExpandedURI (q<DOMCore:read-only>)).q[}],
                perl_statement
                  (perl_exception
                     class => 'DOMException',
                     type => 'NO_MODIFICATION_ALLOWED_ERR',
                     param => {}),
                $t;
      } else {
        $r .= $t;
      }
    } elsif ($_->local_name eq 'Overridden') {
      $r = perl_statement perl_exception
                     class => 'ManakaiDOMImplementationException',
                     type => 'MDOM_DEBUG_BUG',
                     param => {
                       ExpandedURI q<MDOM_EXCEPTION:values> => {
                         msg => q<This class defines only the interface; >.
                                q<some other class must inherit this class >.
                                q<and implement this subroutine.>,
                       },
                     };
    } elsif ($_->local_name eq 'Type') {
      #
    } else {
      valid_err qq{Element type "@{[$_->local_name]}" not supported},
        node => $_;
    }
  }
  if (defined $node->value and length $node->value) {
    valid_err q{DIS has value}, node => $node;
  }
  $r;
} # dis2perl

{
use re 'eval';
our $Element;
$Element = qr/[A-Za-z0-9]+(?>:(?>[^<>]*)(?>(?>[^<>]+|<(??{$Element})>)*))?/;
my $MElement = qr/([A-Za-z0-9]+)(?>:((?>[^<>]*)(?>(?>[^<>]+|<(??{$Element})>)*)))?/;
  
sub disdoc2text ($;%);
sub disdoc2text ($;%) {
  my ($s, %opt) = @_;
  $s =~ s/\x0D\x0A/\x0A/g;
  $s =~ tr/\x0D/\x0A/;
  my @s = split /\x0A\x0A+/, $s;
  my @r;
  for my $s (@s) {
    if ($s =~ s/^\{([0-9A-Za-z-]+)::\s*//) { ## Start tag'ed element
      my $et = $1;
      if ($et eq 'P') { ## Paragraph
        push @r, (disdoc_inline2text ($s, %opt));
      } elsif ($et eq 'LI' or $et eq 'OLI') { ## List
        my $marker = '* ';
        if ($et eq 'OLI') {
          $marker = '# ';
        }
        if ($s =~ s/^(.+?)::\s*//) {
          $marker = disdoc_inline2text ($1, %opt) . ': ';
        }
        push @r, $marker . (disdoc_inline2text ($s, %opt));
      } else {
        valid_err qq<Unknown DISDOC element type "$et">, node => $opt{node};
      }
    } elsif ($s =~ /^\}\s*$/) { ## End tag
      #
    } elsif ($s =~ s/^([-=])\s*//) { ## List
      my $marker = $1;
      if ($marker eq '=') {
        $marker = '# ';
      } elsif ($marker eq '-') {
        $marker = '* ';
      }
      if ($s =~ s/^(.+?)::\s*//) {
        $marker = disdoc_inline2text ($1, %opt) . ': ';
      }
      push @r, $marker . (disdoc_inline2pod ($s, %opt));
    } elsif ($s =~ /^[^\w\s<]/) { ## Reserved for future extension
      valid_err qq<Broken DISDOC: "$s">, node => $opt{node};
    } else {
      $s =~ s/^\s+//;
      push @r, disdoc_inline2text ($s, %opt);
    }
  }
  join "\n\n", @r;
} # disdoc2text

sub disdoc_inline2text ($;%);
sub disdoc_inline2text ($;%) {
  my ($s, %opt) = @_;
  $s =~ s{\G(?:([^<>]+)|<$MElement>|(.))}{
    my ($cdata, $type, $data, $err) = ($1, $2, defined $3 ? $3 : '', $4);
    my $r = '';
    if (defined $err) {
      valid_err qq<Invalid character "$err" in DISDOC>,
        node => $opt{node};
    } elsif (defined $cdata) {
      $r = $cdata;
    } elsif ({DFN => 1, CITE => 1}->{$type}) {
      $r = disdoc_inline2text $data;
    } elsif ({SRC => 1}->{$type}) {
      $r = q<[>. disdoc_inline2text ($data) . q<]>;
    } elsif ({URI => 1}->{$type}) {
      $r = q{<} . $data . q{>};
    } elsif ({CODE => 1, Perl => 1}->{$type}) {
      $r = q<"> . disdoc_inline2text ($data) . q<">;
    } elsif ({IF => 1, TYPE => 1, P => 1, XML => 1, SGML => 1, DOM => 1,
              FeatureVer => 1, CHAR => 1, HTML => 1, Prefix => 1,
              Module => 1, QUOTE => 1, PerlModule => 1,
              FILE => 1}->{$type}) {
      $r = q<"> . $data . q<">;
    } elsif ({Feature => 1, CP => 1, ERR => 1,
              HA => 1, HE => 1, XA => 1, SA => 1, SE => 1}->{$type}) {
      $r = qname_label (undef, qname => $data,
                        no_default_ns => 1);
    } elsif ({Q => 1, EV => 1, 
              XE => 1}->{$type}) {
      $r = qname_label (undef, qname => $data);
    } elsif ({M => 1, A => 1, X => 1, WARN => 1}->{$type}) {
      if ($data =~ /^([^.]+)\.([^.]+)$/) {
        $r = q<"> . $1 . '->' . $2 . q<">;
      } else {
        $r = q<"> . $data . q<">;
      }
    } elsif ({InfosetP => 1}->{$type}) {
      $r = q<[> . $data . q<]>;
    } elsif ($type eq 'lt') {
      $r = '<';
    } elsif ($type eq 'gt') {
      $r = '>';
    } else {
      valid_err qq<DISDOC element type "$type" not supported>,
        node => $opt{node};
    }
    $r;
  }ges;
  $s;
} # disdoc_inline2text

sub disdoc2pod ($;%);
sub disdoc2pod ($;%) {
  my ($s, %opt) = @_;
  $s =~ s/\x0D\x0A/\x0A/g;
  $s =~ tr/\x0D/\x0A/;
  my @s = split /\x0A\x0A+/, $s;
  my @el = ({type => '#document'});
  my @r;
  for my $s (@s) {
    if ($s =~ s/^\{([0-9A-Za-z-]+)::\s*//) { ## Start tag'ed element
      my $et = $1;
      if ($el[-1]->{type} eq '#list' and
          not {qw/LI 1 OLI 1/}->{$et}) {
        push @r, '=back';
        pop @el;
      }
      push @el, {type => $et};
      if ($et eq 'P') { ## Paragraph
        push @r, pod_para (disdoc_inline2pod ($s, %opt));
      } elsif ($et eq 'LI' or $et eq 'OLI') { ## List
        my $marker = '*';
        unless ($el[-1]->{type} eq '#list') {
          push @el, {type => '#list', n => 0};
          push @r, '=over 4';
        }
        if ($et eq 'OLI') {
          $marker = ++($el[-1]->{n}) . '. ';
        }
        if ($s =~ s/^(.+?)::\s*//) {
          $marker = disdoc_inline2pod ($1, %opt);
        }
        push @r, pod_item ($marker), pod_para (disdoc_inline2pod ($s, %opt));
      } else {
        valid_err qq<Unknown DISDOC element type "$et">, node => $opt{node};
      }
    } elsif ($s =~ /^\}\s*$/) { ## End tag
      while (@el > 1 and $el[-1]->{type} =~ /^\#/) {
        if ($el[-1]->{type} eq '#list') {
          push @r, '=back';
        }
        pop @el;
      }
      if ($el[-1]->{type} eq '#document') {
        valid_err qq<Unmatched DISDOC end tag>, node => $opt{node};
      } else {
        pop @el;
      }
    } elsif ($s =~ s/^([-=])\s*//) { ## List
      my $marker = $1;
      unless ($el[-1]->{type} eq '#list') {
        push @el, {type => '#list', n => 0};
        push @r, '=over 4';
      }
      if ($marker eq '=') {
        $marker = ++($el[-1]->{n}) . '. ';
      } elsif ($marker eq '-') {
        $marker = '*';
      }
      if ($s =~ s/^(.+?)::\s*//) {
        $marker = disdoc_inline2pod ($1, %opt);
      }
      push @r, pod_item ($marker), pod_para (disdoc_inline2pod ($s, %opt));
    } elsif ($s =~ /^[^\w\s<]/) { ## Reserved for future extension
      valid_err qq<Broken DISDOC: "$s">, node => $opt{node};
    } else {
      if ($el[-1]->{type} eq '#list') {
        push @r, '=back';
        pop @el;
      }
      $s =~ s/^\s+//;
      push @r, pod_para disdoc_inline2pod ($s, %opt);
    }
  }
  while (@el and $el[-1]->{type} =~ /^\#/) {
    if ($el[-1]->{type} eq '#list') {
      push @r, '=back';
    }
    pop @el;
  }
  if (@el) {
    valid_err qq[DISDOC end tag required for "$el[-1]->{type}"],
        node => $opt{node};
  }
  wantarray ? @r : join "\n\n", @r;
} # disdoc2pod

sub disdoc_inline2pod ($;%);
sub disdoc_inline2pod ($;%) {
  my ($s, %opt) = @_;
  $s =~ s{\G(?:([^<>]+)|<$MElement>|(.))}{
    my ($cdata, $type, $data, $err) = ($1, $2, defined $3 ? $3 : '', $4);
    my $r = '';
    if (defined $err) {
      valid_err qq<Invalid character "$err" in DISDOC>,
        node => $opt{node};
    } elsif (defined $cdata) {
      $r = pod_cdata $cdata; 
    } elsif ({CODE => 1}->{$type}) {
      $r = pod_code disdoc_inline2pod $data;
    } elsif ({DFN => 1}->{$type}) {
      $r = pod_dfn disdoc_inline2pod $data;
    } elsif ({CITE => 1}->{$type}) {
      $r = q[I<] . disdoc_inline2pod ($data) . q[>];
    } elsif ({SRC => 1}->{$type}) {
      $r = q<[>. disdoc_inline2pod ($data) . q<]>;
    } elsif ({URI => 1}->{$type}) {
      $r = pod_uri $data;
    } elsif ({
              IF => 1, TYPE => 1, P => 1, DOM => 1, XML => 1, HTML => 1,
              SGML => 1, FeatureVer => 1, CHAR => 1, Prefix => 1,
              Perl => 1, FILE => 1,
             }->{$type}) {
      $r = pod_code $data;
    } elsif ({Feature => 1, CP => 1, ERR => 1,
              HA => 1, HE => 1, XA => 1, SA => 1, SE => 1}->{$type}) {
      $r = qname_label (undef, qname => $data,
                        out_type => ExpandedURI q<lang:pod>,
                        no_default_ns => 1);
    } elsif ({Q => 1, EV => 1, 
              XE => 1}->{$type}) {
      $r = qname_label (undef, qname => $data,
                        out_type => ExpandedURI q<lang:pod>);
    } elsif ({
              M => 1, A => 1,
             }->{$type}) {
      if ($data =~ /^([^.]+)\.([^.]+)$/) {
        $r = pod_code ($1 . '->' . $2);
      } else {
        $r = pod_code $data;
      }
    } elsif ({X => 1, WARN => 1}->{$type}) {
      if ($data =~ /^([^.]+)\.([^.]+)$/) {
        $r = pod_code ($1) . '.' . pod_code ($2);
      } else {
        $r = pod_code $data;
      }
    } elsif ({InfosetP => 1}->{$type}) {
      $r = q<[> . $data . q<]>;
    } elsif ({QUOTE => 1}->{$type}) {
      $r = q<"> . $data . q<">;
    } elsif ({PerlModule => 1}->{$type}) {
      $r = pod_link label => pod_code ($data), module => $data;
    } elsif ({Module => 1}->{$type}) {
      $r = pod_link label => pod_code ($data),
                    module => perl_package_name (name => $data);
    } elsif ($type eq 'lt' or $type eq 'gt') {
      $r = qq<E<$type>>;
    } else {
      valid_err qq<DISDOC element type "$type" not supported>,
        node => $opt{node};
    }
    $r;
  }ges;
  $s;
}
}

sub get_description ($;%) {
  my ($node, %opt) = @_;
  my $ln = $opt{name} || 'Description';
  my $lang = $opt{lang} || q<en> || q<i-default>;
  my $textplain = ExpandedURI q<DOMMain:any>;
  my $default = q<lang:disdoc>;
  $opt{type} ||= ExpandedURI q<lang:pod>;
  my $script = $opt{script} || q<>;
  my $def;
  for my $type (($opt{type} ne $textplain ? $opt{type} : ()),
                ExpandedURI q<lang:disdoc>,
                $textplain) {
    $def = $node->get_element_by (sub {
      my ($me, $you) = @_;
      $you->local_name eq $ln and
      $you->get_attribute_value ('lang', default => 'i-default') eq $lang and
      type_expanded_uri ($you->get_attribute_value ('Type', default => $default))
        eq $type;
    }) || $node->get_element_by (sub {
      my ($me, $you) = @_;
      $you->local_name eq $ln and
      $you->get_attribute_value ('lang', default => 'i-default')
                                 eq 'i-default' and
      type_expanded_uri ($you->get_attribute_value ('Type', default => $default))
        eq $type;
    });
    last if $def;
  }
  unless ($def) {
    $opt{default};
  } else {
    my $srctype = type_expanded_uri 
                    $def->get_attribute_value ('Type', default => $default);
    my $value = $def->value;
    valid_err q<Description undefined>, node => $def
      unless defined $value;
    if ($srctype eq ExpandedURI q<lang:disdoc>) {
      if ($opt{type} eq ExpandedURI q<lang:pod>) {
        $value = $opt{is_inline} ?
                   disdoc_inline2pod ($value, node => $def):
                   disdoc2pod ($value, node => $def);
      } else {
        $value = $opt{is_inline} ?
                   disdoc_inline2text ($value, node => $def):
                   disdoc2text ($value, node => $def); 
        if ($opt{type} eq ExpandedURI q<lang:muf>) {
          $value =~ s/\s+/ /g;
        }
      }
    } elsif ($srctype eq ExpandedURI q<lang:muf>) {
      if ($opt{type} eq ExpandedURI q<lang:muf>) {
        $value = muf_template $value;
        $value =~ s/\s+/ /g;
      } else {
        impl_err q<Can't convert MUF tempalte to >.$opt{type};
      }
    } elsif ($srctype eq $opt{type}) {
      # 
    } else {
      if ($opt{type} eq ExpandedURI q<lang:pod>) {
        $value = pod_paras $def->value;
      } elsif ($opt{type} eq ExpandedURI q<lang:muf>) {
        $value =~ s/%/%percent;/g;
        $value =~ s/\s+/ /g;
      }
    }
    $value;
  }
}

sub get_level_description ($%) {
  my ($node, %opt) = @_;
  my @l = @{$node->get_attribute_value ('SpecLevel', default => [],
                                        as_array => 1)};
  unless (@l) {
    my $min = $opt{level}->[0] || 1;
    for ($min..$MAX_DOM_LEVEL) {
      if ($Info->{Condition}->{'DOM' . $_}) {
        unshift @l, $_;
        last;
      }
    }
  }
  return q<> unless @l;
  @l = sort {$a <=> $b} @l;
  @{$opt{level}} = @l;
  my $r = q<introduced in DOM Level > . (0 + shift @l);
  if (@l > 1) {
    my $s = 0 + pop @l;
    $r .= q< and modified in DOM Levels > . join ', ', @l;
    $r .= qq< and $s>;
  } elsif (@l == 1) {
    $r .= q< and modified in DOM Level > . (0 + $l[0]);
  }
  $r;
} # get_level_description

sub get_alternate_description ($;%) {
  my ($node, %opt) = @_;
  my @desc;
  $opt{if} ||= 'interface';
  $opt{method} ||= $node->local_name =~ /Attr/ ? 'attribute' : 'method';
  
  ## XML Namespace unaware alternate
  ## (This method is namespace aware.)
  my $ns = $node->get_attribute_value ('NoNSVersion', as_array => 1,
                                       default => undef);
  if (defined $ns) {
    my $a = '';
    if (@$ns) {
      $a = english_list 
             [map {
               if (/^(?:[AM]:)?([^.]+)\.([^.]+)$/) {
                 pod_code ($2) . ' on the interface '.
                 type_label (type_expanded_uri ($1), is_pod => 1)
               } else {
                 pod_code ($_)
               }
             } @$ns], connector => 'and/or';
      $a = qq<DOM applications dealing with documents that do >.
           qq<not use XML Namespaces should use $a instead.>;
    }
    push @desc, pod_para
                  qq<This $opt{method} is namespace-aware.  Mixing >.
                  qq<namespace-aware and -unaware methods can lead >.
                  qq<to unpredictable result.  $a>;
  }

  ## XML Namespace aware alternate
  ## (This method is namespace unaware.)
  $ns = $node->get_attribute_value ('NSVersion', as_array => 1,
                                       default => undef);
  if (defined $ns) {
    my $a = '';
    if (@$ns) {
      $a = english_list 
             [map {
               if (/^(?:[AM]:)?([^.]+)\.([^.]+)$/) {
                 pod_code ($2) . ' on the interface '.
                 type_label (type_expanded_uri ($1), is_pod => 1)
               } else {
                 pod_code ($_)
               }
             } @$ns];
      $a = qq<DOM applications dealing with documents that do >.
           qq<use XML Namespaces should use $a instead.>;
    }
    push @desc, pod_para
                  qq<This $opt{method} is namespace ignorant.  Mixing >.
                  qq<namespace-aware and -unaware methods can lead >.
                  qq<to unpredictable result.  $a>;
  }

  @desc;
} # get_alternate_description

sub get_redef_description ($;%) {
  my ($node, %opt) = @_;
  my @desc;
  $opt{if} ||= 'interface';
  $opt{method} ||= 'method';
  if ($node->local_name eq 'ReMethod' or
      $node->local_name eq 'ReAttr') {
    my $redef = $node->get_attribute_value ('Redefine');
    push @desc, pod_para qq<This $opt{method} is defined by the >.
                         ($redef ? qq<$opt{if} > . type_label
                                                    (type_expanded_uri ($redef),
                                                     is_pod => 1)
                                 : qq<super-$opt{if} of this $opt{if}>).
                         q< but that definition has been overridden here.>;
  }
  if ($node->get_attribute_value ('IsAbstract', default => 0)) {
    push @desc, pod_para (qq<This $opt{method} is defined abstractly; >.
                          qq<it must be overridden by cocrete implementation. >);
  }
    my @redefBy;
    for (@{$node->child_nodes}) {
      next unless $_->node_type eq '#element' and
                  $_->local_name eq 'RedefinedBy';
      push @redefBy, type_label (type_expanded_uri ($_->value), is_pod => 1);
    }
    if (@redefBy) {
      push @desc, pod_para qq<This $opt{method} is redefined by the >.
                           qq<implementation of the sub-$opt{if}>.
                           (@redefBy > 1 ? 's ' : ' ').
                           english_list (\@redefBy, connector => 'and').'.';
    }
  @desc;
} # get_redef_description;

sub get_isa_description ($;%) {
  my ($node, %opt) = @_;
  $opt{if} ||= $node->get_attribute_value ('IsAbstract', default => 0)
                          ? 'interface' : 'class';
  my @desc;
  my @isa;
  my @impl;
  for (@{$node->child_nodes}) {
    next unless $_->node_type eq '#element';
    if ($_->local_name eq 'ISA') {
      my $v = $_->value;
      if (type_expanded_uri $_->get_attribute_value ('Type',
                                                     default => 'DOMMain:any') eq
          ExpandedURI q<lang:Perl>) {
        push @isa, pod_link (module => $v);
      } else {
        $v =~ s/::[^:]*$//g;
        push @isa, type_label (type_expanded_uri ($v), is_pod => 1);
      }
    } elsif ($_->local_name eq 'Implement') {
      my $v = $_->value;
      $v =~ s/::[^:]*$//g;
      push @impl, type_label (type_expanded_uri ($v), is_pod => 1);
    }
  }
  if (@isa and @impl) {
    push @desc, pod_para (qq<This $opt{if} inherits >.
                          english_list (\@isa, connector => 'and').
                          qq< and implements >.
                          (@impl>1?q<interfaces >:q<the interface >).
                          english_list (\@impl, connector => 'and').q<.>);
  } elsif (@isa) {
    push @desc, pod_para (qq<This $opt{if} inherits >.
                          english_list (\@isa, connector => 'and').q<.>);
  } elsif (@impl) {
    push @desc, pod_para (qq<This $opt{if} implements >.
                          (@impl>1?q<interfaces >:q<the interface >).
                          english_list (\@impl, connector => 'and').q<.>);
  }
  @desc;
} # get_isa_description

sub get_incase_label ($;%) {
  my ($node, %opt) = @_;
  my $label = $node->get_attribute_value ('Label', default => '');
  unless (length $label) {
    $label = $node->get_attribute ('Value'); 
    my $type = type_normalize
                 type_expanded_uri
                    ($node->get_attribute_value ('Type') ||
                     $node->parent_node->get_attribute_value
                                                ('Type',
                                                 default => q<DOMMain:any>));
    if ($label) {
      if ($label->get_attribute_value ('is-null', default => 0)) {
        $label = 'null';
      } else {
        if (not defined $label->value) {
          valid_err q<Value is null>, node => $node;
        }
        if (type_isa $type, ExpandedURI q<DOMMain:DOMString>) {
          $label = perl_literal $label->value;
        } else {
          $label = $label->value;
        }
      }
      $label = $opt{is_pod} ? pod_code $label : $label;
    } else {
      $label = type_label $type, is_pod => $opt{is_pod};
    }
  } else {
    $label = get_description $node, name => 'Label', is_inline => 1;
  }
  $label;
}

sub get_value_literal ($%) {
  my ($node, %opt) = @_;
  my $value = get_perl_definition_node $node, %opt;
  my $type = type_normalize type_expanded_uri
               $node->get_attribute_value ($opt{type_name} || 'Type',
                                           default => q<DOMMain:any>);
  my $r;
  if ($type eq ExpandedURI q<DOMMain:boolean>) {
    if ($value) {
      $r = ($value->value and $value->value eq 'true') ? 1 : 0;
    } else {
      $r = $opt{default} ? 1 : 0;
    }
  } elsif ($type eq ExpandedURI q<DOMMain:unsigned-long> or
           $type eq ExpandedURI q<DOMMain:unsigned-long-long> or
           $type eq ExpandedURI q<DOMMain:long> or
           $type eq ExpandedURI q<DOMMain:float> or
           $type eq ExpandedURI q<DOMMain:unsigned-short>) {
    if ($value) {
      $r = $value->value;
    } else {
      $r = defined $opt{default} ? $opt{default} : 0;
    }
  } elsif (type_isa $type, ExpandedURI q<DOMMain:DOMString>) {
    if ($value) {
      if ($value->get_attribute_value ('is-null', default => 0)) {
        $r = 'undef';
      } else {
        $r = perl_literal $value->value;
      }
    } else {
      if (exists $opt{default}) {
        $r = defined $opt{default} ? perl_literal $opt{default} : 'undef';
      } else {
        $r = perl_literal '';
      }
    }
  } elsif ($type eq ExpandedURI q<Perl:ARRAY>) {
    if ($value) {
      $r = perl_literal $value->value (as_array => 1);
    } else {
      $r = perl_literal (defined $opt{default} ? $opt{default} : []);
    }
  } elsif ($type eq ExpandedURI q<Perl:HASH>) {
    if ($value) {
      $r = perl_literal $value->value;
    } else {
      $r = perl_literal (defined $opt{default} ? $opt{default} : {});
    }
  } else {
    if ($value) {
      if ($value->get_attribute_value ('is-null', default => 0)) {
        $r = 'undef';
      } else {
        $r = perl_literal $value->value;
      }
    } else {
      if (exists $opt{default}) {
        $r = defined $opt{default} ? perl_literal $opt{default} : 'undef';
      } else {
        $r = 'undef';
      }
    }
  }
  $r;
}

sub get_internal_code ($$;%) {
  my ($node, $name, %opt) = @_;
  $node = $node->parent_node;
  my $m;
  my $def;
  if ($m = $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->node_type eq '#element' and
    ($you->local_name eq 'Method' or
     $you->local_name eq 'ReMethod') and
    $you->get_attribute_value ('Name') eq $name
  })) {
    $def = $m->get_attribute ('Return');
    $def = (get_perl_definition_node $def, name => 'IntDef', use_dis => 1 or
            get_perl_definition_node $def, name => 'Def', use_dis => 1) if $def;
  } elsif ($m = $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->node_type eq '#element' and
    ($you->local_name eq 'Attr' or
     $you->local_name eq 'ReAttr') and
    $you->get_attribute_value ('Name') eq $name
  })) {
    $def = $m->get_attribute ('Get');
    $def = (get_perl_definition_node $def, name => 'IntDef', use_dis => 1 or
            get_perl_definition_node $def, name => 'Def', use_dis => 1) if $def;
  } elsif ($m = $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->node_type eq '#element' and
    $you->local_name eq 'IntMethod' and
    $you->get_attribute_value ('Name') eq $name
  })) {
    $def = $m->get_attribute ('Return');
    $def = get_perl_definition_node $def, name => 'Def', use_dis => 1 if $def;
  } elsif ($m = $node->get_element_by (sub {
    my ($me, $you) = @_;
    $you->node_type eq '#element' and
    $you->local_name eq 'IntAttr' and
    $you->get_attribute_value ('Name') eq $name
  })) {
    $def = $m->get_attribute ('Get');
    $def = get_perl_definition_node $def, name => 'Def', use_dis => 1 if $def;
  }
  if ($def) {
    if (type_expanded_uri ($def->get_attribute_value ('Type', default => ''))
            eq ExpandedURI q<lang:dis>) {
      return dis2perl $def;
    } else {
      return perl_code $def->value;
    }
  } else {
    valid_warn qq<Internal method "$name" not defined>;
    is_implemented (if => $Status->{IF}, method => $name, set => 0);
    $Status->{is_implemented} = 0;
    return perl_statement perl_exception
                  level => 'EXCEPTION',
                  class => 'DOMException',
                  type => 'NOT_SUPPORTED_ERR',
                  param => {
                    ExpandedURI q<MDOM_EXCEPTION:if> => $Status->{IF},
                    ExpandedURI q<MDOM_EXCEPTION:method> => $name,
                  };
  }
} # get_internal_code

sub register_namespace_declaration ($) {
  my $node = shift;
  for (@{$node->child_nodes}) {
    if ($_->node_type eq '#element' and
        $_->local_name eq 'Namespace') {
      for (@{$_->child_nodes}) {
        $Info->{Namespace}->{$_->local_name} = $_->value;
      }
    }
  }
}

{
my $nest = 0;
sub is_implemented (%);
sub is_implemented (%) {
  my (%opt) = @_;
  my $r = 0;
  $nest++ == 100 and valid_err q<Condition loop detected>;
  my $member = ($Info->{is_implemented}->{$opt{if}}->{$opt{method} ||
                                                     $opt{attr} . '.' . $opt{on}}
            ||= {});
  if (exists $opt{set}) {
    $r = ($member->{$opt{condition} || ''} = $opt{set});
  } else {
    if (defined $member->{$opt{condition} || ''}) {
      $r = $member->{$opt{condition} || ''};
    } else {
      for (@{$Info->{Condition}->{$opt{condition} || ''}->{ISA} || []}) {
        if (is_implemented (%opt, condition => $_)) {
          $r = 1;
          last;
        }
      }
    }
  }
  $nest--;
  $r;
}
sub is_all_implemented (%);
sub is_all_implemented (%) {
  my (%opt) = @_;
  $nest++ == 100 and valid_err q<Condition loop detected>;
  $opt{not_implemented} ||= [];
    IF: for my $if (keys %{$Info->{is_implemented}}) {
      for my $mem (keys %{$Info->{is_implemented}->{$if}}) {
        ## Note: In fact, this checks whether the method is NOT implemented
        ##       rather than the method IS implemented.
        if (exists $Info->{is_implemented}->{$if}->{$mem}->{$opt{condition}} and
            not $Info->{is_implemented}->{$if}->{$mem}->{$opt{condition}}) {
          @{$opt{not_implemented}} = ($if, $mem, $opt{condition} || '');
          last IF;
        }
      }
    }
  if (not @{$opt{not_implemented}}) {
    for (@{$Info->{Condition}->{$opt{condition} || ''}->{ISA} || []}) {
      if (not is_all_implemented (%opt, condition => $_)) {
        last;
      }
    }
  }
  @{$opt{not_implemented}} ? 0 : 1;
}}

sub condition_match ($%) {
  my ($node, %opt) = @_;
  my $conds = $node->get_attribute_value ('Condition', default => [],
                                          as_array => 1);
  my $level = $node->get_attribute_value
                        ('Level',
                         default_list => @$conds ? []
                                                 : ($opt{level_default} || []),
                         as_array => 1);
  for (@$conds) {
    unless ($Info->{Condition}->{$_}) {
      valid_err qq<Condition "$_" not defined>;
    }
  }
  for (@$level) {
    unless ($Info->{Condition}->{"DOM".$_}) {
      valid_err qq<Condition "DOM$_" not defined>;
    }
  }
  if (not $opt{condition}) {
    if (@$conds == 0 and @$level == 0) {
      return 1;
    } elsif (array_contains $conds, '$normal') {
      return 1;
    } elsif ($opt{ge} and not @$conds) {
      return 1;
    } elsif ($opt{any_unless_condition}) {
      return 1;
    } else {
      return 0;
    }
  } else {
    if (array_contains $conds, $opt{condition}) {
      return 1;
    } elsif ($opt{condition} =~ /^DOM(\d+)$/) {
      if ($opt{ge}) {
        for (my $i = $1; $i; $i--) {
          if (array_contains $level, $i) {
            return 1;
          }
        }
      } else {
        if ($1 and array_contains $level, $1) {
          return 1;
        }
      }
    }
    ## 'default_any': Match to 'any' condition (no condition specified)
    if ($opt{default_any} and @$conds == 0 and @$level == 0) {
      return 1;
    }
    return 0;
  }
}

=head1 SOURCE FORMAT

"Dis" (DOM implementation source) file is written in
SuikaWikiConfig/2.0 text format.

=head2 IF element

C<IF> element defines a DOM interface with its descriptions
and implementations.

Children elements:

=over 4

=item IF/Name = name (1 - 1)

Interface name.  It should be taken from DOM specification.

=item IF/Description = text (0 - infinite)

Description for the interface.

=item IF/ISA[list] = list of names (0 - 1)

Names of interfaces that this interface inherits.

=item IF/Method, IF/IntMethod, IF/ReMethod

Method definition.

=item IF/Attr, IF/IntAttr, IF/ReAttr

Attribute definition.

=item IF/ConstGroup

Constant value group definition.

=item IF/Const

Constant value definition.

=back

=cut

sub if2perl ($) {
  my $node = shift;
  local $Status->{depth} = $Status->{depth} + 1;
  my $pack_name = perl_package_name
                    name => my $if_name
                               = perl_name $node->get_attribute_value ('Name'),
                                           ucfirst => 1;
  my $if_pack_name = perl_package_name if => $if_name;
  my $iif_pack_name = perl_package_name iif => $if_name;
  local $Status->{IF} = $if_name;
  local $Status->{if} = {}; ## Temporary data
  local $Info->{Namespace} = {%{$Info->{Namespace}}};
  local $Info->{Require_perl_package} = {%{$Info->{Require_perl_package}}};
  local $Info->{Require_perl_package_use} = {};
  local $Status->{is_implemented} = 1;
  my $is_abs = $node->get_attribute ('IsAbstract', default => 0);
  my $is_fin = $node->get_attribute ('IsFinal', default => 0);
  $is_fin = -1 if $is_abs;           # 1=no subclass, 0=free, -1=must be subclass
  my $impl_by_app = $node->get_attribute ('ImplByApp', default => 0);

  my @level;
  my $mod = get_level_description $node, level => \@level;

  push my @desc,
               pod_head ($Status->{depth}, 'Interface ' . pod_code ($if_name).
                         ($is_abs?'':', Class '.pod_code ($pack_name)));

  push @desc, pod_paras (get_description ($node));
  push @desc, pod_para ('This interface is ' . $mod . q<.>) if $mod;

  if ($impl_by_app) {
    push @desc, pod_para ('This interface is intended to be implemented '.
                          'by DOM applications.  To implement this '.
                          'interface, put the statement '),
                pod_pre ('push our @ISA, q<'.($is_abs?$if_name:$pack_name).'>;'),
                pod_para ('on your package and define methods and '.
                          'attributes.');
  }

  push @desc, get_isa_description ($node);

  my $result = pod_block @desc;

  my $has_role = $node->get_attribute ('Role');
  
  for my $condition ((sort keys %{$Info->{Condition}}), '') {
    if ($condition =~ /^DOM(\d+)$/) {
      next if @level and $level[0] > $1;
    }
    local $Status->{Operator} = {};
    local $Status->{condition} = $condition;
    my $cond_if_pack_name = perl_package_name if => $if_name,
                                    condition => $condition;
    my $cond_iif_pack_name = perl_package_name iif => $if_name,
                                    condition => $condition;
    my $cond_pack_name = perl_package_name name => $if_name,
                                    condition => $condition;
    my $cond_int_pack_name = perl_package_name name => $if_name,
                                    condition => $condition,
                                    is_internal => 1;
    my $cond_iint_pack_name = perl_package_name name => $if_name,
                                    condition => $condition,
                                    is_internal => 1,
                                    is_for_inheriting => 1;
    $result .= perl_package full_name => $cond_int_pack_name;
    my @isa;
    for (@{$node->child_nodes}) {
      next unless $_->node_type eq '#element' and
                  condition_match $_, condition => $condition,
                                      default_any => 1, ge => 1;
      if ($_->local_name eq 'ISA') {
        if (type_expanded_uri ($_->get_attribute_value ('Type',
                                     default => ExpandedURI q<DOMMain:any>))
            eq ExpandedURI q<lang:Perl>) {
          my $v = $_->value;
          if ($v =~ /[^\w:]|(?<!:):(?!:)/) {
            valid_err q<Invalid package name "$v">, node => $_;
          }
          push @isa, $v;
        } else {
          push @isa, perl_package_name qname_with_condition => $_->value,
                                       condition => $condition,
                                       is_internal => 1,
                                       is_for_inheriting => 1;
        }
      } elsif ($_->local_name eq 'Implement') {
        push @isa, perl_package_name if_qname_with_condition => $_->value,
                                     condition => $condition;
      }
    }
    push my @isag, perl_package_name (name => 'ManakaiDOMObject')
      unless $if_name eq 'ManakaiDOMObject';
    my @isaa;
    if ($condition) {
      for (@{$Info->{Condition}->{$condition}->{ISA}}) {
        push @isaa, perl_package_name name => $if_name,
                                     condition => $_,
                                     is_internal => 1;
      }
      $result .= perl_inherit [$cond_int_pack_name, @isaa, @isa, @isag]
                                              => $cond_pack_name;
      $result .= perl_inherit [@isaa, $cond_iif_pack_name]
                                              => $cond_int_pack_name;
      $result .= perl_inherit [$cond_int_pack_name, @isa]
                                              => $cond_iint_pack_name;
      $result .= perl_inherit [$cond_if_pack_name, $iif_pack_name]
                                              => $cond_iif_pack_name;
      $result .= perl_inherit [$if_pack_name] => $cond_if_pack_name;
    } else { ## No condition specified
      $result .= perl_inherit [$cond_int_pack_name, @isa, @isag]
                                              => $cond_pack_name;
      if ($Info->{NormalCondition}) {
        push @isaa, perl_package_name name => $if_name,
                                     condition => $Info->{NormalCondition},
                                     is_internal => 1;
        $result .= perl_inherit [@isaa]
                              => $cond_int_pack_name;
      } else {  ## Condition not used
        $result .= perl_inherit [$iif_pack_name] => $cond_int_pack_name;
      }
      $result .= perl_inherit [$cond_int_pack_name, @isa]
                              => $cond_iint_pack_name;
      $result .= perl_inherit [$if_pack_name] => $iif_pack_name;
    }
    for my $pack ($cond_pack_name, $cond_int_pack_name,
                  $cond_iif_pack_name, $cond_if_pack_name,
                  $cond_iint_pack_name) {
      $result .= perl_statement perl_assign
                   perl_var (type => '$',
                             package => {full_name => $pack},
                             local_name => 'VERSION')
                   => version_date time;
    }

    my @feature;
    for (@{$node->child_nodes}) {
      my $gt = 0;
      unless (condition_match $_, level_default => \@level,
                                  condition => $condition) {
        if (condition_match $_, level_default => \@level,
                                condition => $condition, ge => 1) {
          $gt = 1;
        } else {
          next;
        }
      }
      
      if ($_->local_name eq 'Method' or
          $_->local_name eq 'IntMethod' or
          $_->local_name eq 'ReMethod') {
        $result .= method2perl ($_, level => \@level, condition => $condition)
          unless $gt;
      } elsif ($_->local_name eq 'Attr' or
               $_->local_name eq 'IntAttr' or
               $_->local_name eq 'ReAttr') {
        $result .= attr2perl ($_, level => \@level, condition => $condition)
          unless $gt;
      } elsif ($_->local_name eq 'ConstGroup') {
        $result .= constgroup2perl ($_, level => \@level,
                                    condition => $condition,
                                    without_document => $gt,
                                    package => $cond_int_pack_name);
      } elsif ($_->local_name eq 'Const') {
        $result .= const2perl ($_, level => \@level, condition => $condition,
                               package => $cond_int_pack_name)
          unless $gt;
      } elsif ($_->local_name eq 'Require') {
        $result .= req2perl ($_, level => \@level, condition => $condition);
      } elsif ($_->local_name eq 'Feature') {
        push @feature, $_;
      } elsif ({qw/Name 1 Spec 1 ISA 1 Description 1 Implement 1
                   Level 1 SpecLevel 1 ImplNote 1 Role 1
                   IsAbstract 1 IsFinal 1 ImplByApp 1/}->{$_->local_name}) {
        #
      } else {
        valid_warn qq{Element @{[$_->local_name]} not supported};
      }
    }

    if ($has_role) {
      my $role = type_expanded_uri $has_role->value;
      if ($role eq ExpandedURI q<DOMCore:DOMImplementationSource>) {
        $result .= perl_statement
                     q<push @org::w3c::dom::DOMImplementationSourceList, >.
                     perl_literal $cond_pack_name;
      } else {
        my $var = q<@{>.perl_var (type => '$',
                            local_name => $ManakaiDOMModulePrefix.'::Role').
                  q<{>.perl_literal ($role).q<}}>;
        my %prop;
        if ($has_role->get_attribute ('compat')) {
          $prop{compat} = type_expanded_uri
                            $has_role->get_attribute_value ('compat');
        } else {
          $prop{compat} = '';
        }
        $result .= perl_statement
                     'push '.$var.q<, >.
                     perl_list {
                       class => $cond_pack_name,
                       constructor => 'new',
                       %prop,
                     };
      }
    }

    if (@feature or $has_role) {
      $result .= '{' . perl_statement 'our $Feature';
      for (@feature) {
        my $name = $_->get_attribute ('QName');
                              if ($name) {
                                $name = type_expanded_uri ($name->value);
                              } else {
                                $name = $_->get_attribute_value ('Name');
                              }
        $result .= perl_statement '$Feature->{'.perl_literal ($name).'}->{'.
                   perl_literal ($_->get_attribute_value ('Version')).
                   '} = 1';
      }

      $result .= perl_sub
                   name => '___classHasFeature',
                   prototype => '$%',
                   code => 
                     perl_statement ('my ($self, %f) = @_').
                     q[
                       for (keys %f) {
                         if ($Feature->{$_}) {
                           if (defined $f{$_}->{version}) {
                             delete $f{$_}
                               if $Feature->{$_}->{$f{$_}->{version}};
                           } else {
                             delete $f{$_} if keys %{$Feature->{$_}};
                           }
                           return 1 if keys (%f) == 0;
                         }
                       }
                     ].
                     (@isa + @isaa ?
                     q[for (].perl_list (@isa, @isaa).q[) {
                       if (my $c = $_->can ('___classHasFeature')) {
                         if ($c->($self, %f)) {
                           return 1;
                         }
                       }
                     }] : '').
                     (($has_role and $has_role->get_attribute ('compat'))?
                     q[
                       my %g;
                       for (keys %f) {
                         unless ($f{$_}->{plus}) {
                           return 0;
                         } else {
                           $g{$_} = {version => $f{$_}->{version}};
                         }
                       }
                       for (reverse @{$].$ManakaiDOMModulePrefix.'::Role{'.
                            perl_literal (type_expanded_uri
                                            $has_role->value).'}'.q[||[]}) {
                         if ($_->{compat} eq ].
                             perl_literal ($has_role->get_attribute_value
                                               ('compat')).q[) {
                           if ($_->{class}->___classHasFeature (%g)) {
                             return 1;
                           }
                         }
                       }
                     ]:'').
                     perl_statement (q<return 0>);
      $result .= '}';
    } 
    
    $result .= ops2perl;
  }

  $result;
} # if2perl

=head2 Method, IntMethod and ReMethod elements

C<Method>, C<IntMethod> and C<ReMethod> element defines a method.
Methods defined by C<Method> are ones as defined in the DOM
specification.  Methods defined by C<IntMethod> are only for
internal use and usually not defined by the specifications.
Methods defined by C<ReMethod> do actually not belong
to this interface but to ancestor interface in the specification
but overriddenly re-defined for this type of descendant interfaces
(for example, some methods defined in Node interface of the DOM
Core Module are re-defined in Element, Attr or other node-type
interfaces, since those methods work differently by type of
the node).

Children elements:

=over 4

=item Name = name (1 - 1)

Method name.  It should be taken from DOM specification
if element type is C<Method> or C<ReMethod>.  Method name
for C<ReMethod> must be used as the name of the C<Method>
defined in ancestor interface.  Method name for C<IntMethod>
must be different with any other C<Method>, C<IntMethod>
or C<ReMethod> (including those defined by ancestor interfaces).

=item Description = text (0 - infinite)

Description for the method.

=back

=cut

sub method2perl ($;%) {
  my ($node, %opt) = @_;
  local $Status->{depth} = $Status->{depth} + 1;
  my $m_name = perl_name $node->get_attribute_value ('Name');
  my $level;
  my @level = @{$opt{level} || []};
  local $Status->{Method} = $m_name;
  local $Status->{is_implemented} = 1;
  my $result = '';
  if ($node->local_name eq 'IntMethod') {
    $m_name = perl_internal_name $m_name;
    $level = '';
  } else {
    $level = get_level_description $node, level => \@level;
  }
  
  my @param_list;
  my $param_prototype = '$';
  my @param_desc;
  my @param_domstring;
  if ($node->get_attribute ('Param')) {
    for (@{$node->child_nodes}) {
      if ($_->local_name eq 'Param') {
        my $name = perl_name $_->get_attribute_value ('Name');
        my $type = type_expanded_uri $_->get_attribute_value
                                            ('Type',
                                             default => 'DOMMain:any');
        push @param_list, '$' . $name;
        push @param_desc, pod_item (pod_code '$' . $name);
        if (type_isa $type, ExpandedURI q<ManakaiDOM:ManakaiDOMNamespaceURI>) {
          push @param_domstring, [$name, $type];
        }
        push my @param_desc_val,
                          pod_item (type_label $type, is_pod => 1),
                          pod_para get_description $_;
        $param_prototype .= '$';
        for (@{$_->child_nodes}) {
          next unless $_->local_name eq 'InCase';
          push @param_desc_val, pod_item (get_incase_label $_, is_pod => 1),
                                pod_para (get_description $_);
        }
        push @param_desc, pod_list 4, @param_desc_val;
      }
    }
  }
  
  my $return = $node->get_attribute ('Return');
  unless ($return) {
    ## NOTE: A method without return value does not have 'Return'
    ##       before its code is implemented.
    valid_warn q<Required "Return" element not found>, node => $node;
    $return = $node->get_attribute ('Return', make_new_node => 1);
  }
  my $has_return = $return->get_attribute_value ('Type', default => 0) ? 1 : 0;
  push my @desc,
               pod_head ($Status->{depth}, 'Method ' . 
                         pod_code (($has_return ? '$return = ' : '') .
                         '$obj->' . $m_name .
                         ' (' . join (', ', @param_list) . ')')),
               pod_paras (get_description ($node)),
               $level ? pod_para ('The method ' . pod_code ($m_name) .
                           q< has been > . $level . '.') : ();

  if (@param_list) {
    push @desc, pod_para ('This method requires ' .
                          english_number (@param_list + 0,
                                          singular => q<parameter>,
                                          plural => q<parameters>) . ':'),
                pod_list (4, @param_desc);                           
  } else {
    push @desc, pod_para (q<This method has no parameter.>);
  }

  my $is_abs = $node->get_attribute_value ('IsAbstract', default => 0);
  if ($is_abs) {
    unless (get_perl_definition_node $return, 
                              condition => $opt{condition},
                              level_default => $opt{level_default},
                              use_dis => 1) {
      for ($return->append_new_node (type => '#element',
                                     local_name => 'Def')) {
        $_->set_attribute ('Type' => ExpandedURI q<lang:dis>);
        $_->set_attribute ('Overridden' => 1);
      }
    }
  }

  my @return;
  my @exception;
  my $has_exception = 0;
  my $code_node = get_perl_definition_node $return,
                              condition => $opt{condition},
                              level_default => $opt{level_default},
                              use_dis => 1;
  my $int_code_node = get_perl_definition_node $return, name => 'IntDef',
                              condition => $opt{condition},
                              level_default => $opt{level_default},
                              use_dis => 1;
  my $code;
  my $int_code;
  for ({code => \$code, code_node => $code_node,
        internal => sub {
          return get_internal_code $node, $_[0] if $_[0];
          if ($int_code_node) {
            perl_code $int_code_node->value,
              internal => sub {
                $_[0] ? get_internal_code $node, $_[0] :
                valid_err q<Preprocessing macro INT cannot be used here>;
              };
          } else {
            valid_err "<IF[Name = $Status->{IF}]/Method[Name = $m_name]/" .
                      "Return/IntDef> required";
          }
        }},
       {code => \$int_code, code_node => $int_code_node,
        internal => sub {$_[0]?get_internal_code $node,$_[0]:
                         valid_err q<Preprocessing macro INT cannot be> .
                                   q<used here>}}) {
    if ($_->{code_node}) {
      my $mcode;
      if (type_expanded_uri ($_->{code_node}->get_attribute_value
                                       ('Type', default => q<DOMMain:any>))
            eq ExpandedURI q<lang:dis>) {
        $mcode = dis2perl $_->{code_node};
      } else {
        $mcode = perl_code $_->{code_node}->value,
                           internal => $_->{internal};
      }
      if ($mcode =~ /^\s*$/) {
        ${$_->{code}} = '';
      } else {
        ${$_->{code}} = perl_code_source ($mcode,
                                          path => $_->{code_node}->node_path
                                                              (key => 'Name'));
      }
    }
  }
  if ($code_node) {
    if ($has_return) {
      $code = perl_statement (perl_assign 'my $r' => get_value_literal $return,
                                                        name => 'DefaultValue',
                                                        type_name => 'Type') .
              $code;
      if ($code_node->get_attribute_value ('cast-output', default => 1)) {
        my $type = type_normalize
              type_expanded_uri $return->get_attribute_value
                                         ('Type',
                                          default => q<DOMMain:any>);
        if (type_isa $type, ExpandedURI q<ManakaiDOM:ManakaiDOMNamespaceURI>) {
          $code .= perl_builtin_code $type,
                                     s => 'r', r => 'r',
                                     condition => $opt{condition};
        }
      }
      $code .= perl_statement ('$r');
    } else {
      $code .= perl_statement ('undef');
    }
    if ($code_node->get_attribute_value ('auto-argument', default => 1)) {
      if ($code_node->get_attribute_value ('cast-input', default => 1)) {
        for (@param_domstring) {
          $code = perl_builtin_code ($_->[1],
                                     s => $_->[0], r => $_->[0],
                                     condition => $opt{condition}) . $code;
        }
      }
      $code = perl_statement (perl_assign 'my (' .
                                          join (', ', '$self', @param_list) .
                                          ')' => '@_') .
              $code;
    }
    if ($int_code_node) {
      if ($has_return) {
        $int_code = perl_statement (perl_assign 'my $r' => perl_literal '') .
                    $int_code .
                    perl_statement ('$r');
      } else {
        $int_code .= perl_statement ('undef');
      }
      $int_code = perl_statement (perl_assign 'my (' .
                                        join (', ', '$self', @param_list) .
                                        ')' => '@_') .
                  $int_code
         if $int_code_node->get_attribute_value ('auto-argument', default => 1);
    }

    if ($has_return) {
      push @return, pod_item (type_label (type_expanded_uri
                                     ($return->get_attribute_value
                                                ('Type',
                                                 default => 'DOMMain:any')),
                                          is_pod => 1)),
                    pod_para (get_description $return);
    }
    for (@{$return->child_nodes}) {
      if ($_->local_name eq 'InCase') {
        push @return, pod_item ( get_incase_label $_, is_pod => 1),
                      pod_para (get_description $_);
        $has_return++;
      } elsif ($_->local_name eq 'Exception') {
        push @exception, pod_item ('Exception: ' .
                                     (type_label ($_->get_attribute_value
                                                   ('Type',
                                                    default => 'DOMMain:any'),
                                                      is_pod => 1)).
                                '.' . pod_code $_->get_attribute_value
                                                   ('Name',
                                                    default => '<unknown>')),
                      pod_para (get_description $_);
        my @st;
        for (@{$_->child_nodes}) {
          next unless $_->node_type eq '#element';
          if ($_->local_name eq 'SubType') {
            push @st, subtype2poditem ($_);
          } elsif ({qw/Name 1 Type 1
                       Description 1 ImplNote 1
                       Condition 1 Level 1 SpecLevel 1/}->{$_->local_name}) {
            # 
          } else {
            valid_err qq{Element type "@{[$_->local_name]}" not supported},
              node => $_;
          }
        }
        push @exception, pod_list 4, @st if @st;
        $has_exception++;
      }
    }
  } else {
    $Status->{is_implemented} = 0;
    $int_code = $code
              = perl_statement ('my $self = shift').
                perl_statement perl_exception
                  level => 'EXCEPTION',
                  class => 'DOMException',
                  type => 'NOT_SUPPORTED_ERR',
                  param => {
                    ExpandedURI q<MDOM_EXCEPTION:if> => $Status->{IF},
                    ExpandedURI q<MDOM_EXCEPTION:method> => $Status->{Method},
                  };
    @return = ();
    push @exception, pod_item ('Exception: ' . pod_code ('DOMException') . '.' .
                            pod_code ('NOT_SUPPORTED_ERR')),
                  pod_para ('Call of this method allways result in
                             this exception raisen, since this
                             method is not implemented yet.');
    $has_return = 0;
    $has_exception = 1;
  }
  is_implemented if => $Status->{IF}, method => $Status->{Method},
                 condition => $opt{condition}, set => $Status->{is_implemented};
  if ($has_return or $has_exception) {
    if ($has_return) {
      push @desc, pod_para (q<This method results in > .
                           ($has_return == 1 ? q<the value:>
                                             : q<either:>)),
                  pod_list 4, pod_item (pod_code q<$return>),
                              pod_list (4, @return),
                              @exception;
    } elsif ($has_exception) {
      push @desc, pod_para (q<This method does not return any value,
                              but it might raise > .
                            ($has_exception == 1 ? q<an exception:>
                                                 : q<one of exceptions from:>)),
                  pod_list 4, @exception;
    }
  } else {
    push @desc, pod_para q<This method does not return any value
                           nor does raise any exceptions.>;
  }

  push @desc, get_alternate_description $node;
  push @desc, get_redef_description $node;

  if ($node->local_name eq 'IntMethod' or
      $Status->{if}->{method_documented}->{$m_name}++) {
    $result .= pod_block pod_comment @desc;
  } else {
    $result .= pod_block @desc;
  }
  
  $result .= perl_sub name => $m_name,
                      prototype => $param_prototype,
                      code => $code;
  $result .= perl_sub name => perl_internal_name $m_name,
                      prototype => $param_prototype,
                      code => $int_code
     if $int_code_node;

  if (my $op = get_perl_definition_node $node, name => 'Operator') {
    my $value = $op->value;
    valid_err qq{Overloaded operator name not specified},
      node => $op
      unless defined $value;
    $Status->{Operator}->{$value} = '\\' . perl_var type => '&', 
                                                        local_name => $m_name;
  }

  $result;
} # method2perl

sub attr2perl ($;%) {
  my ($node, %opt) = @_;
  local $Status->{depth} = $Status->{depth} + 1;
  my $m_name = perl_name $node->get_attribute_value ('Name');
  my $level;
  my @level = @{$opt{level} || []};
  local $Status->{Method} = $m_name;
  local $Status->{is_implemented} = 1;
  my $result = '';
  if ($node->local_name eq 'IntAttr') {
    $m_name = perl_internal_name $m_name;
    $level = '';
  } else {
    $level = get_level_description $node, level => \@level;
  }
  
  my $return = $node->get_attribute ('Get');
  unless ($return) {
    valid_err q<Required "Get" element not found>, node => $node;
  }
  my $set = $node->get_attribute ('Set');
  my $has_set = defined $set ? 1 : 0;
  push my @desc,
               pod_head ($Status->{depth}, 'Attribute ' . 
                         pod_code ('$obj->' . $m_name)),
               pod_paras (get_description ($node)),
               $level ? pod_para ('The method ' . pod_code ($m_name) .
                           q< has been > . $level . '.') : ();

  my $is_abs = $node->get_attribute_value ('IsAbstract', default => 0);
  if ($is_abs) {
    unless (get_perl_definition_node $return, 
                              condition => $opt{condition},
                              level_default => $opt{level_default},
                              use_dis => 1) {
      for ($return->append_new_node (type => '#element',
                                     local_name => 'Def')) {
        $_->set_attribute ('Type' => ExpandedURI q<lang:dis>);
        $_->set_attribute ('Overridden' => 1);
      }
    }
  }  

  my $code_node = get_perl_definition_node $return,
                              condition => $opt{condition},
                              level_default => $opt{level_default},
                              use_dis => 1;
  my $int_code_node = get_perl_definition_node $return, name => 'IntDef',
                              condition => $opt{condition},
                              level_default => $opt{level_default},
                              use_dis => 1;
  my ($set_code_node, $int_set_code_node);
  if ($has_set) {
    if ($is_abs) {
      unless (get_perl_definition_node $set, 
                                condition => $opt{condition},
                                level_default => $opt{level_default},
                                use_dis => 1) {
        for ($return->append_new_node (type => '#element',
                                       local_name => 'Def')) {
          $_->set_attribute ('Type' => ExpandedURI q<lang:dis>);
          $_->set_attribute ('Overridden' => 1);
        }
      }
    }  
    $set_code_node = get_perl_definition_node $set,
                              condition => $opt{condition},
                              level_default => $opt{level_default},
                              use_dis => 1;
    $int_set_code_node = get_perl_definition_node $set, name => 'IntDef',
                              condition => $opt{condition},
                              level_default => $opt{level_default},
                              use_dis => 1;
  }
  my $code = '';
  my $int_code = '';
  my $set_code = '';
  my $int_set_code = '';
  for ({code => \$code, code_node => $code_node,
        internal => sub {
          return get_internal_code $node, $_[0] if $_[0];
          if ($int_code_node) {
            perl_code $int_code_node->value,
              internal => sub {
                $_[0] ? get_internal_code $node, $_[0] :
                valid_err q<Preprocessing macro INT cannot be used here>;
              };
          } else {
            valid_err "<IF[Name = $Status->{IF}]/Attr[Name = $m_name]/" .
                      "Get/IntDef> required";
          }
        }},
       {code => \$int_code, code_node => $int_code_node,
        internal => sub {$_[0]?get_internal_code $node,$_[0]:
                         valid_err q<Preprocessing macro INT cannot be> .
                                   q<used here>}},
       {code => \$set_code, code_node => $set_code_node,
        internal => sub {
          return get_internal_code $node, $_[0] if $_[0];
          if ($int_set_code_node) {
            perl_code $int_set_code_node->value,
              internal => sub {
                $_[0] ? get_internal_code $node, $_[0] :
                valid_err q<Preprocessing macro INT cannot be used here>;
              };
          } else {
            valid_err "<IF[Name = $Status->{IF}]/Attr[Name = $m_name]/" .
                      "Set/IntDef> required";
          }
        }},
       {code => \$int_set_code, code_node => $int_set_code_node,
        internal => sub {$_[0]?get_internal_code $node,$_[0]:
                         valid_err q<Preprocessing macro INT cannot be> .
                                   q<used here>}}) {
    if ($_->{code_node}) {
      my $mcode;
      if (type_expanded_uri ($_->{code_node}->get_attribute_value
                                       ('Type', default => q<DOMMain:any>))
            eq ExpandedURI q<lang:dis>) {
        $mcode = dis2perl $_->{code_node};
      } else {
        $mcode = perl_code $_->{code_node}->value,
                           internal => $_->{internal},
                           node => $_->{code_node};
      }
      if ($mcode =~ /^\s*$/) {
        ${$_->{code}} = '';
      } else {
        ${$_->{code}} = perl_code_source ($mcode,
                                          path => $_->{code_node}->node_path
                                                              (key => 'Name'));
      }
    }
  }

  my @return;
  my @return_xcept;
  if ($code_node) {
    is_implemented if => $Status->{IF}, attr => $Status->{Method},
                   condition => $opt{condition}, set => 1, on => 'get';
    my $co = $code_node->get_attribute_value ('cast-output',
                                              default => $code eq '' ? 0 : 1);
    if ($code eq '' and not $co) {
      $code = perl_statement get_value_literal $return,
                                               name => 'DefaultValue',
                                               type_name => 'Type';
    } else {
      $code = perl_statement (perl_assign 'my $r' => get_value_literal $return,
                                                        name => 'DefaultValue',
                                                        type_name => 'Type') .
              $code;
      if ($co) {
        my $type = type_normalize
              type_expanded_uri $return->get_attribute_value
                                         ('Type',
                                          default => q<DOMMain:any>);
        if (type_isa $type, ExpandedURI q<ManakaiDOM:ManakaiDOMNamespaceURI>) {
          $code .= perl_builtin_code $type,
                                     s => 'r', r => 'r',
                                     condition => $opt{condition};
        }
      }
      $code .= perl_statement ('$r');
    }
    $code = get_warning_perl_code ($return) . $code;
    if ($int_code_node) {
      $int_code = perl_statement (perl_assign 'my $r' => perl_literal '') .
                  $int_code .
                  perl_statement ('$r');
      $int_code = perl_statement (perl_assign 'my ($self)' => '@_') . $int_code
         if $int_code_node->get_attribute_value ('auto-argument', default => 1);
    }

    push @return, pod_item (type_label (type_expanded_uri
                                     $return->get_attribute_value
                                                ('Type',
                                                 default => 'DOMMain:any'),
                                          is_pod => 1)),
                    pod_para (get_description $return);
    for (@{$return->child_nodes}) {
      if ($_->local_name eq 'InCase') {
        push @return, pod_item (get_incase_label $_, is_pod => 1),
                      pod_para (get_description $_);
      } elsif ($_->local_name eq 'Exception') {
        push @return_xcept, pod_item ('Exception: ' .
                                (type_label ($_->get_attribute_value
                                                   ('Type',
                                                    default => 'DOMMain:any'),
                                                      is_pod => 1)) .
                                '.' . pod_code $_->get_attribute_value
                                                   ('Name',
                                                    default => '<unknown>')),
                      pod_para (get_description $_);
        my @st;
        for (@{$_->child_nodes}) {
          next unless $_->node_type eq '#element';
          if ($_->local_name eq 'SubType') {
            push @st, subtype2poditem ($_);
          } elsif ({qw/Name 1 Type 1
                       Description 1 ImplNote 1
                       Condition 1 Level 1 SpecLevel 1/}->{$_->local_name}) {
            # 
          } else {
            valid_err qq{Element type "@{[$_->local_name]}" not supported},
              node => $_;
          }
        }
        push @return_xcept, pod_list 4, @st if @st;
      }
    }
  } else {
    is_implemented if => $Status->{IF}, attr => $Status->{Method},
                   condition => $opt{condition}, set => 0, on => 'get';
    $Status->{is_implemented} = 0;
    $int_code = $code
              = perl_statement perl_exception
                  level => 'EXCEPTION',
                  class => 'DOMException',
                  type => 'NOT_SUPPORTED_ERR',
                  param => {
                    ExpandedURI q<MDOM_EXCEPTION:if> => $Status->{IF},
                    ExpandedURI q<MDOM_EXCEPTION:attr> => $Status->{Method},
                    ExpandedURI q<MDOM_EXCEPTION:on> => 'get',
                  };
    @return = ();
    push @return_xcept,
                  pod_item ('Exception: ' . pod_code ('DOMException') . '.' .
                            pod_code ('NOT_SUPPORTED_ERR')),
                  pod_para ('Getting of this attribute allways result in
                             this exception raisen, since this
                             attribute is not implemented yet.');
  }
  push @desc, pod_para ('DOM applications can get the value by:'),
              pod_pre (qq{\$return = \$obj->$m_name}),
              pod_list (4,
                        @return ? (pod_item pod_code q<$return>,
                                   pod_list 4, @return): (),
                        @return_xcept);

  my @set_desc;
  my @set_xcept;
  if ($set_code_node) {
    is_implemented if => $Status->{IF}, attr => $Status->{Method},
                   condition => $opt{condition}, set => 1, on => 'set';
    if ($set_code_node->get_attribute_value ('cast-input',
                                         default => $set_code eq '' ? 0 : 1)) {
      my $type = type_normalize
              type_expanded_uri $set->get_attribute_value
                                         ('Type',
                                          default => q<DOMMain:any>);
      if (type_isa $type, ExpandedURI q<ManakaiDOM:ManakaiDOMNamespaceURI>) {
        $set_code = perl_builtin_code ($type,
                                       s => 'given', r => 'given',
                                       condition => $opt{condition})
                  . $set_code;
      }
    }
    $set_code = get_warning_perl_code ($set) . $set_code;

    push @set_desc, pod_item (type_label (type_expanded_uri
                                     ($set->get_attribute_value
                                                ('Type',
                                                 default => 'DOMMain:any')),
                                          is_pod => 1)),
                    pod_para (get_description $set);
    for (@{$set->child_nodes}) {
      if ($_->local_name eq 'InCase') {
        push @set_desc, pod_item (get_incase_label $_, is_pod => 1),
                        pod_para (get_description $_);
      } elsif ($_->local_name eq 'Exception') {
        push @set_xcept, pod_item ('Exception: ' .
                                (type_label ($_->get_attribute_value
                                                   ('Type',
                                                    default => 'DOMMain:any'),
                                                      is_pod => 1)) .
                                '.' . pod_code $_->get_attribute_value
                                                   ('Name',
                                                    default => '<unknown>')),
                      pod_para (get_description $_);
        my @st;
        for (@{$_->child_nodes}) {
          next unless $_->node_type eq '#element';
          if ($_->local_name eq 'SubType') {
            push @st, subtype2poditem ($_);
          } elsif ({qw/Name 1 Type 1
                       Description 1 ImplNote 1
                       Condition 1 Level 1 SpecLevel 1/}->{$_->local_name}) {
            # 
          } else {
            valid_err qq{Element type "@{[$_->local_name]}" not supported},
              node => $_;
          }
        }
        push @set_xcept, pod_list 4, @st if @st;
      }
    }
  } elsif ($has_set) {
    is_implemented if => $Status->{IF}, attr => $Status->{Method},
                   condition => $opt{condition}, set => 0, on => 'set';
    $Status->{is_implemented} = 0;
    $int_set_code = $set_code
              = perl_statement perl_exception
                  level => 'EXCEPTION',
                  class => 'DOMException',
                  type => 'NOT_SUPPORTED_ERR',
                  param => {
                    ExpandedURI q<MDOM_EXCEPTION:if> => $Status->{IF},
                    ExpandedURI q<MDOM_EXCEPTION:attr> => $Status->{Method},
                    ExpandedURI q<MDOM_EXCEPTION:on> => 'set',
                  };
    @set_desc = pod_item '(Not implemented yet)';
    @set_xcept = ();
    push @set_xcept, pod_item ('Exception: ' . pod_code ('DOMException') . '.' .
                            pod_code ('NOT_SUPPORTED_ERR')),
                  pod_para ('Setting of this attribute allways result in
                             this exception raisen, since this
                             attribute is not implemented yet.');
  }
  
  if ($has_set) {
    push @desc, pod_para ('DOM applications can set the value by:'),
                pod_pre (qq{\$obj->$m_name (\$newValue)}),
                pod_list 4, 
                  pod_item (pod_code q<$newValue>),
                  pod_list 4, @set_desc;
    push @desc, (@set_xcept ?
                    (pod_para (q<Setting this attribute may raise exception:>),
                     pod_list (4, @set_xcept)) :
                    (pod_para (q<Setting this attribute does not raise >.
                               q<exception in general.>)));
  } else {
    push @desc, pod_para ('This attribute is read-only.');
  }
  is_implemented if => $Status->{IF}, method => $Status->{Method},
                 condition => $opt{condition}, set => $Status->{is_implemented};

  push @desc, get_alternate_description $node;
  push @desc, get_redef_description $node, method => 'attribute';

  if ($node->local_name eq 'IntAttr' or
      $Status->{if}->{method_documented}->{$m_name}++) {
    $result .= pod_block pod_comment @desc;
  } else {
    $result .= pod_block @desc;
  }
  
  my $warn = get_warning_perl_code ($node);
  my $proto;
  if ($has_set) {
    $code = perl_statement (perl_assign
              perl_var (scope => 'my', type => '$', local_name => 'self')
               => 'shift').
            $warn.
            perl_if
              q<exists $_[0]>,
              ($set_code =~/\bgiven\b/ ?
                    perl_statement (q<my $given = shift>) : '') . $set_code .
              perl_statement ('undef'),
              $code;
    $int_code = perl_statement (perl_assign
              perl_var (scope => 'my', type => '$', local_name => 'self')
               => 'shift').
            perl_if
              q<exists $_[0]>,
              perl_statement (q<my $given = shift>) . $int_set_code,
              $int_code;
    $proto = '$;$';
  } else {
    $code = q<my $self = shift; > . $warn . $code;
    $int_code = q<my $self = shift; > . $int_code;
    $proto = '$';
  }
  $result .= perl_sub name => $m_name,
                      prototype => $proto,
                      code => $code;
  $result .= perl_sub name => perl_internal_name $m_name,
                      prototype => $proto,
                      code => $int_code
     if $int_code_node;

  if (my $op = get_perl_definition_node $node, name => 'Operator') {
    $Status->{Operator}->{$op->value} = '\\' . perl_var type => '&', 
                                                        local_name => $m_name;
  }

  $result;
} # attr2perl

=head2 DataType element

The C<DataType> element defines a datatype.

=cut

sub datatype2perl ($;%) {
  my ($node, %opt) = @_;
  local $Status->{depth} = $Status->{depth} + 1;
  my $pack_name = perl_package_name
                    name => my $if_name
                                 = perl_name $node->get_attribute_value ('Name'),
                                             ucfirst => 1;
  local $Status->{IF} = $if_name;
  local $Status->{if} = {}; ## Temporary data
  local $Info->{Namespace} = {%{$Info->{Namespace}}};
  local $Info->{Require_perl_package} = {%{$Info->{Require_perl_package}}};
  local $Info->{Require_perl_package_use} = {};
  local $Status->{Operator} = {};
  my $result = perl_package full_name => $pack_name;
  my @isa;
  for (@{$node->child_nodes}) {
    next unless $_->node_type eq '#element' and
                $_->local_name eq 'ISA' and
                condition_match $_, condition => $opt{condition},
                                    default_any => 1, ge => 1;
    push @isa, perl_package_name qname_with_condition => $_->value,
                                 condition => $opt{condition};
  }
  $result .= perl_inherit [@isa, perl_package_name (name => 'ManakaiDOMObject'),
                           perl_package_name (if => $if_name)];
  for my $pack ({full_name => $pack_name}, {if => $if_name}) {
    $result .= perl_statement perl_assign
                 perl_var (type => '$',
                           package => $pack,
                           local_name => 'VERSION')
                 => version_date time;
  }
  
  my @level = @{$opt{level} || []};
  my $mod = get_level_description $node, level => \@level;
  $result .= pod_block
               pod_head ($Status->{depth}, 'Type ' . pod_code $if_name),
               pod_paras (get_description ($node)),
               ($mod ? pod_para ('This type is ' . $mod) : ());

  for (@{$node->child_nodes}) {
    if ($_->local_name eq 'Method' or
        $_->local_name eq 'IntMethod') {
      $result .= method2perl ($_, level => \@level, 
                              condition => $opt{condition});
    } elsif ($_->local_name eq 'Attr' or
             $_->local_name eq 'IntAttr') {
      $result .= attr2perl ($_, level => \@level, condition => $opt{condition});
    } elsif ($_->local_name eq 'ConstGroup') {
      $result .= constgroup2perl ($_, level => \@level, 
                                  condition => $opt{condition},
                                  package => $pack_name);
    } elsif ($_->local_name eq 'Const') {
      $result .= const2perl ($_, level => \@level,
                             condition => $opt{condition},
                             package => $pack_name);
    } elsif ($_->local_name eq 'ISA') {
      push @{$Info->{DataTypeAlias}->{type_expanded_uri $if_name}
                  ->{isa_uri}||=[]},
           type_expanded_uri $_->value;
    } elsif ({qw/Name 1 FullName 1 Spec 1 Description 1
                 Level 1 SpecLevel 1 Def 1 ImplNote 1/}->{$_->local_name}) {
      #
    } else {
      valid_warn qq{Element @{[$_->local_name]} not supported};
    }
  }

  $result .= ops2perl;

  $result;
} # datatype2perl

sub datatypealias2perl ($;%) {
  my ($node, %opt) = @_;
  local $Status->{depth} = $Status->{depth} + 1;
  my $if_name = $node->get_attribute_value ('Name');
  my $long_name = expanded_uri $if_name;
  my $real_long_name = type_expanded_uri
                         (my $real_name = $node->get_attribute_value
                                             ('Type', default => 'DOMMain:any'));
  if (type_label ($real_long_name) eq type_label ($long_name)) {
    $Info->{DataTypeAlias}->{$long_name}->{canon_uri} = $real_long_name;
    return perl_comment sprintf '%s <%s> := %s <%s>',
                                type_label ($long_name), $long_name,
                                type_label ($real_long_name), $real_long_name;
  }
  $Info->{DataTypeAlias}->{$long_name}->{canon_uri} = $real_long_name;
  
  $if_name = perl_name $if_name, ucfirst => 1;
  $real_name = type_package_name $real_name;
  my $pack_name = perl_package_name name => $if_name;
  local $Status->{IF} = $if_name;
  local $Status->{if} = {}; ## Temporary data
  local $Info->{Namespace} = {%{$Info->{Namespace}}};
  local $Info->{Require_perl_package} = {%{$Info->{Require_perl_package}}};
  local $Info->{Require_perl_package_use} = {};
  my $result = perl_package full_name => $pack_name;
  $result .= perl_inherit [perl_package_name (full_name => $real_name),
                           perl_package_name (if => $if_name)];
  for my $pack ({if => $if_name}) {
    $result .= perl_statement perl_assign
                 perl_var (type => '$',
                           package => $pack,
                           local_name => 'VERSION')
                 => version_date time;
  }
  
  my @level = @{$opt{level} || []};
  my $mod = get_level_description $node, level => \@level;
  $result .= pod_block
               pod_head ($Status->{depth}, 'Type ' . pod_code $if_name),
               pod_paras (get_description ($node)),
               pod_para ('This type is an alias of the type ' .
                         (type_label $real_long_name, is_pod => 1) . '.'),
               ($mod ? pod_para ('This type is ' . $mod) : ());

  for (@{$node->child_nodes}) {
    if ({qw/Name 1 FullName 1 Spec 1 Type 1 Description 1
            Level 1 SpecLevel 1 Condition 1 ImplNote 1
            Def 1/}->{$_->local_name}) {
      #
    } else {
      valid_warn qq{Element @{[$_->local_name]} not supported};
    }
  }

  $result;
} # datatypealias2perl

=item Exception top-level element

=item Warning top-level element

=cut

sub exception2perl ($;%) {
  my ($node, %opt) = @_;
  local $Status->{depth} = $Status->{depth} + 1;
  local $Status->{const} = {};
  local $Status->{if} = {}; ## Temporary data
  local $Status->{in_exception} = 1;
  local $Info->{Namespace} = {%{$Info->{Namespace}}};
  local $Info->{Require_perl_package} = {%{$Info->{Require_perl_package}}};
  local $Info->{Require_perl_package_use} = {};
  my $pack_name = perl_package_name
                    name => my $if_name
                                 = perl_name $node->get_attribute_value ('Name'),
                                             ucfirst => 1;
  my $type = $node->local_name eq 'Exception' ? 'Exception' : 'Warning';
  local $Status->{IF} = $if_name;
  my $result = perl_package full_name => $pack_name;
  $result .= perl_statement perl_assign 'our $VERSION', version_date time;
  my @isa = perl_package_name (if => $if_name);
  if ($if_name eq 'ManakaiDOM'.$type) {
    push @isa, perl_package_name name => 'ManakaiDOMExceptionOrWarning';
  } elsif ($if_name eq 'ManakaiDOMExceptionOrWarning') {
    push @isa, 'Message::Util::Error';
  } else {
    push @isa, perl_package_name name => 'ManakaiDOM'.$type
  }
  $result .= perl_inherit [@isa];
  $result .= perl_statement perl_assign
                   perl_var (type => '$',
                             package => {if => $if_name},
                             local_name => 'VERSION')
                   => version_date time;
  my @level = @{$opt{level} || []};
  my $mod = get_level_description $node, level => \@level;
  $result .= pod_block
               pod_head ($Status->{depth}, $type . ' ' . pod_code $if_name),
               pod_paras (get_description ($node)),
               ($mod ? pod_para ('This ' . lc ($type) . ' is introduced in ' .
                                 $mod . '.') : ()),
               ($type eq 'Exception' ? 
                 (pod_para ('To catch this class of exceptions:'),
                  pod_pre (join "\n",
                           q|try {                                 |,
                           q|  ...                                 |,
                           q|} catch | . $pack_name . q| with {    |,
                           q|  my $err = shift;                    |,
                           q|  if ($err->{type} eq 'ERROR_NAME') { |,
                           q|    ... # Recover from some error,    |,
                           q|  } else {                            |,
                           q|    $err->throw; # rethrow if other   |,
                           q|  }                                   |,
                           q|}; # Don't forget semicolon!          |))
               : ());  

  for (@{$node->child_nodes}) {
    if ($_->local_name eq 'Method' or
        $_->local_name eq 'IntMethod' or
        $_->local_name eq 'ReMethod') {
      $result .= method2perl ($_, level => \@level, 
                              condition => $opt{condition},
                              any_unless_condition => 1);
    } elsif ($_->local_name eq 'Attr' or
             $_->local_name eq 'IntAttr' or
             $_->local_name eq 'ReAttr') {
      my $get;
      if ($_->local_name eq 'Attr' and
          $_->get_attribute_value ('Name') eq 'code' and
          $get = $_->get_attribute ('Get') and
          not get_perl_definition_node $get, name => 'Def') {
        for ($get->append_new_node (type => '#element',
                                    local_name => 'Def',
                                    value => q{
                                      $r = $self->{<Q:ManakaiDOM:code>};
                                    })) {
          $_->set_attribute (type => 'lang:Perl'); ## ISSUE: NS prefix assoc.
        }
      }
      $result .= attr2perl ($_, level => \@level, condition => $opt{condition},
                            any_unless_condition => 1);
    } elsif ($_->local_name eq 'ConstGroup') {
      $result .= constgroup2perl ($_, level => \@level, 
                                  condition => $opt{condition},
                                  package => $pack_name,
                                  any_unless_condition => 1);
    } elsif ($_->local_name eq 'Const') {
      $result .= const2perl ($_, level => \@level,
                             condition => $opt{condition},
                             package => $pack_name,
                             any_unless_condition => 1);
    } elsif ({qw/Name 1 Spec 1 Description 1
                 Level 1 SpecLevel 1 Condition 1
                 ImplNote 1/}->{$_->local_name}) {
      #
    } else {
      valid_warn qq{Element @{[$_->local_name]} not supported};
    }
  }

  $result .= perl_sub
               name => '___error_def', prototype => '',
               code => perl_list {
                 map {
                   $_ => {
                     ExpandedURI q<DOMCore:code> => perl_code_literal
                               ($Status->{const}->{$_}->{code_literal}),
                     description
                            => $Status->{const}->{$_}->{description},
                     ExpandedURI q<MDOM_EXCEPTION:subtype>
                            => $Status->{const}->{$_}->{subtype},
                   }
                 } sort keys %{$Status->{const}}
               };

  $result;
} # exception2perl

sub constgroup2perl ($;%);
sub constgroup2perl ($;%) {
  my ($node, %opt) = @_;
  local $Status->{depth} = $Status->{depth} + 1; 
  my $name = $node->get_attribute ('Name');
  if (defined $name) {
    $name = perl_name $name->value, ucfirst => 1;
  }
  local $Status->{IF} = $name || q<[anonymous constant group]>;
  my @level = @{$opt{level} || []};
  my $mod = get_level_description $node, level => \@level;
  my $result = '';
  my $consts = {};
  $Info->{DataTypeAlias}->{expanded_uri $node->get_attribute_value ('Name')}
       ->{isa_uri} = [type_expanded_uri $node->get_attribute_value
                                         ('Type', default => q<DOMMain:any>)]
         if defined $name;

  my $i = 0;
  {
    local $Status->{EXPORT_OK} = $consts;
    for (@{$node->child_nodes}) {
      my $only_document = $opt{only_document} || 0;
      unless ($_->node_type eq '#element' and
              condition_match $_, level_default => \@level,
                                  condition => $opt{condition},
                                  any_unless_condition
                                            => $opt{any_unless_condition}) {
        $only_document = 1;
      }
      
      if ($_->local_name eq 'ConstGroup') {
        $result .= constgroup2perl ($_, level => \@level, 
                                    condition => $opt{condition},
                                    without_document => $opt{without_document},
                                    only_document => $only_document,
                                    package => $opt{package},
                                    any_unless_condition
                                            => $opt{any_unless_condition});
        $i++;
      } elsif ($_->local_name eq 'Const') {
        $result .= const2perl ($_, level => \@level,
                               condition => $opt{condition},
                               without_document => $opt{without_document},
                               only_document => $only_document,
                               package => $opt{package},
                               any_unless_condition
                                       => $opt{any_unless_condition});
        $i++;
      } elsif ({qw/Name 1 Spec 1 ISA 1 Description 1 Type 1 IsBitMask 1
                   Level 1 SpecLevel 1 Def 1 ImplNote 1
                   FullName 1/}->{$_->local_name}) {
        #
      } else {
        valid_warn qq{Element @{[$_->local_name]} not supported};
      }
    }
  }
  
  for (keys %$consts) {
    $Status->{EXPORT_OK}->{$_} = 1;
    $Status->{EXPORT_TAGS}->{$name}->{$_} = 1 if defined $name;
  }
    
  return $result if $opt{without_document};

  my @desc;
  if (defined $name) {
    push @desc, pod_head $Status->{depth}, 'Constant Group ' . pod_code $name;
  } else {
    push @desc, pod_head $Status->{depth}, 'Constant Group: ' .
                                get_description ($node,
                                                 name => 'FullName');
  }

  push @desc,  pod_paras (get_description ($node)),
               ($mod ? pod_para ('This constant group has been ' . $mod . '.')
                    : ()),
               pod_para ('This constant group has ' .
                         english_number $i, singular => q<value.>,
                                            plural => q<values.>);

  push @desc,  pod_para ('To export all constant values in this group:'),
               pod_pre (perl_statement "use $Info->{Package} qw/:$name/")
                 if defined $name;
  
  $result = pod_block (@desc) . $result;

  $result;
} # constgroup2perl

sub const2perl ($;%) {
  my ($node, %opt) = @_;
  local $Status->{depth} = $Status->{depth} + 1;
  my $name = perl_name $node->get_attribute_value ('Name');
  my $longname = perl_var local_name => $name,
                          package => {full_name => $opt{package} ||
                                                   $Info->{Package}};
  local $Status->{IF} = $name;
  local $Status->{const_subtype} = {};
  my @level = @{$opt{level} || []};
  my $mod = get_level_description $node, level => \@level;
  my @desc;
  unless ($opt{without_document}) {
    @desc =   (pod_head ($Status->{depth}, 'Constant Value ' . pod_code $name),
               pod_paras (get_description ($node)),
               ($mod ? pod_para ('This constant value has been ' . $mod . '.')
                     : ()));
    
    if ($Status->{in_exception}) { ## Is Exception/Warning code
      #
    } else {                       ## Is NOT Exception/Warning code
      push @desc, pod_para ('To export this constant value:'),
                  pod_pre (perl_statement "use $Info->{Package} qw/$name/");
    }

    my @param;
    for (@{$node->child_nodes}) {
      next unless $_->node_type eq '#element';
      if ($_->local_name eq 'Param') {
        if ($Status->{in_exception}) {
          push @param, param2poditem ($_);
        } else {
          valid_err qq{Element "Param" may not be used with non-Exception}.
                    qq{/Warning constants},
            node => $node;
        }
      } elsif ($_->local_name eq 'SubType') {
        if ($Status->{in_exception}) {
          push @param, subtype2poditem ($_);
        } else {
          valid_err qq{Element "SubType" may not be used with non-Exception}.
                    qq{/Warning constants},
            node => $node;
        }
      } elsif ({qw/Name 1 Spec 1 Description 1
                   Condition 1 Level 1 SpecLevel 1
                   Type 1 Value 1 ImplNote 1/}->{$_->local_name}) {
        #  
      } else {
        valid_err qq{Element type "@{[$_->local_name]}" not supported},
          node => $node;
      }
    }
    push @desc, pod_list 4, @param if @param;
  }
  
  my $result = '';
  unless ($opt{only_document}) {
    $result = perl_sub name => $longname, prototype => '',
                       code => my $code = get_value_literal
                                                $node, name => 'Value';
    $result .= perl_sub name => perl_var (package => {full_name
                                                     => $Info->{Package}},
                                         local_name => $name), prototype => '',
                       code => $code
       if $opt{package} and $Info->{Package} ne $opt{package};
    my $desc_template = get_description $node,
                                      type => ExpandedURI q<lang:muf>,
                                      default => $name;
    $Status->{const}->{$name} = {
      description => $desc_template,
      code_literal => $code,
      subtype => $Status->{const_subtype} || {},
    };
  }

  $Status->{EXPORT_OK}->{$name} = 1;

  unless ($opt{without_document}) {
    $result = pod_block (@desc) . $result;
  }

  $result;
} # const2perl

sub param2poditem ($;%) {
  my ($node, %opt) = @_;
  my @desc;
  $opt{name_prefix} = 'Parameter: ' unless defined $opt{name_prefix};
  if ($node->get_attribute ('Name')) {
    push @desc, $opt{name_prefix} . pod_code $node->get_attribute_value ('Name');
  } elsif ($node->get_attribute ('QName')) {
    push @desc, pod_item $opt{name_prefix} .
                         qname_label ($node,
                                      out_type => ExpandedURI q<lang:pod>);
  } else {
    valid_err q<Attribute "Name" or "QName" required>,
      node => $node;
  }
  
  my @val;
  push @val, pod_item (type_label (type_expanded_uri
                                     ($node->get_attribute_value
                                                ('Type',
                                                 default => 'DOMMain:any')),
                                   is_pod => 1)),
             pod_para (get_description $node);
  for (@{$node->child_nodes}) {
    last unless $_->node_type eq '#element';
    if ($_->local_name eq 'InCase') {
      push @val, pod_item (get_incase_label $_, is_pod => 1),
                 pod_para (get_description $_);
    } elsif ({qw/Name 1 QName 1 Type 1
                 Description 1 ImplNote 1/}->{$_->local_name}) {
      # 
    } else {
      valid_err qq{Element type "@{[$_->local_name]}" not supported},
        node => $_;
    }
  }

  if (@val) {
    push @desc, pod_list 4, @val;
  }

  @desc;
} # param2poditem

sub subtype2poditem ($;%) {
  my ($node, %opt) = @_;
  my @desc;
  $opt{name_prefix} = 'SubType: ' unless defined $opt{name_prefix};
  my $qname = $node->get_attribute_value ('QName');
  if (defined $qname) {
    push @desc, pod_item $opt{name_prefix} .
                qname_label ($node, qname => $qname,
                             out_type => ExpandedURI q<lang:pod>);
  } else {
    valid_err q<Attribute "QName" required>,
      node => $node;
  }
  
  push @desc, pod_para (get_description $node);
  my @param;
  for (@{$node->child_nodes}) {
    last unless $_->node_type eq '#element';
    if ($_->local_name eq 'Param') {
      push @param, param2poditem ($_);
    } elsif ({qw/QName 1 Type 1 SpecLevel 1 
                 Description 1 ImplNote 1/}->{$_->local_name}) {
      # 
    } else {
      valid_err qq{Element type "@{[$_->local_name]}" not supported},
        node => $_;
    }
  }

  if (@param) {
    push @desc, pod_list 4, @param;
  }

  my $desc_template = get_description $node,
                                      type => ExpandedURI q<lang:muf>,
                                      default => $qname;
  $Status->{const_subtype}->{type_expanded_uri $qname} = {
    description => $desc_template,
  };


  @desc;
} # subtype2poditem

=head2 Require element

The C<Require> element indicates that some external modules
are required.  Both DOM-implementing modules and language-specific 
library modules are allowed.

Children:

=over 4

=item Require/Module (0 - infinite)

A required module.

Children:

=over 4

=item Require/Module/Name = name (0 - 1)

The DOM module name.  Iif it is a DOM-implementing module,
this attribute MUST be specified.

=item Require/Module/Namespace = namespace-uri (0 - 1)

The namespace URI for the module, if any.  Namespace prefix
C<Name> is to be binded with C<Namespace> if both
C<Name> and C<Namespace> are available.

=item Require/Module/Def = Type-dependent (0 - infinite)

Language-depending definition of loading of the required module.
If no appropriate C<Type> of C<Def> element is available,
loading code is generated from C<Name> attribute.

=back

=back

=cut

sub req2perl ($) {
  my $node = shift;
  my $reqnode = $node->local_name eq 'Require' ? $node :
                  $node->get_attribute ('Require', make_new_node => 1);
  my $result = '';
  for (@{$reqnode->child_nodes}) {
    if ($_->local_name eq 'Module') {
      my $m_name = $_->get_attribute_value ('Name', default => '<anon>');
      my $ns_uri = $_->get_attribute_value ('Namespace');
      $Info->{Namespace}->{$m_name} = $ns_uri if defined $ns_uri;
      $m_name = perl_name $m_name, ucfirst => 1;
      my $desc = get_description $_;
      $result .= perl_comment (($m_name ne '<anon>' ? $m_name : '') .
                               ($desc ? ' - ' . $desc : ''))
        if $desc or $m_name ne '<anon>';
      my $def = get_perl_definition_node $_, name => 'Def';
      if ($def) {
        my $s;
        my $req;
        my $pack_name;
        if ($req = $def->get_attribute ('require')) {
          $s = 'require ' . ($pack_name = perl_code $req->value);
          $Info->{uri_to_perl_package}->{$ns_uri} = $pack_name if $ns_uri;
          $Info->{Require_perl_package}->{$pack_name} = 1;
        } elsif ($req = $def->get_attribute ('use')) {
          $s = 'use ' . ($pack_name = perl_code $req->value);
          $Info->{uri_to_perl_package}->{$ns_uri} = $pack_name if $ns_uri;
          $Info->{Require_perl_package}->{$pack_name} = 1;
          $Info->{Require_perl_package_use}->{$pack_name} = 1;
        } elsif (defined ($s = $def->value)) {
          # 
        } else {
          valid_warn qq<Required module definition for $m_name is empty>;
        }
        if ($req and my $list = $req->get_attribute_value ('Import',
                                                           as_array => 1)) {
          if (@$list) {
            $s .= ' ' . perl_list @$list;
            $Info->{Require_perl_package_use}
                 ->{$pack_name . '::::Import'}->{$_} = 1 for @$list;
          }
        }
        $result .= perl_statement $s;
      } else {
        $result .= perl_statement 'require ' .
                     perl_code "__CLASS{$m_name}__";
      }
    } elsif ($_->local_name eq 'Condition') {
    } else {
      valid_warn qq[Requiredness type @{[$_->local_name]} not supported];
    }
  }
  $result;
}

=head2 Module element

A "dis" file requires one (and only one) C<Module> top-level element.
Other elements, such as C<Require>, may include C<Module> elements
as their children.

Children:

=over 4

=item Module/Name = name (0 - 1)

The module name.  Usually DOM IDL module name is used.

This attribute is required when C<Module> element is used as
a top-level element.  It is optional if C<Module> is a child
of other element.

=item Module/Package = Type-dependent (0 - infinite)

The module package name.  For example,

  Module:
    @Name: module1
    @Package:
      @@@: Module1
      @@Type:
        lang:Perl

means that general module name is C<module1> and Perl-specific
module name is C<Module1>.

=item Module/Namespace = namespace (1 - 1)

The namespace URI (an absolute URI with optional fragment identifier)
that is assigned to this module.  Datatypes defined by this module
(such as C<DataType> or C<Interface>) are considered to belong to
this namespace.

In addition, the default namespace is binding to this namespace name
(in other word, special namespace prefix C<#default> is associated
with the URI reference).

=item Module/FullName = text (0 - infinite)

A human-readable module name.

=item Module/Description = text (0 - infinite)

A human-readable module description.

=item Module/License = qname (1 - 1)

A qname that identify the license term.

=item Module/Date.RCS = <rcs date> (1 - 1)

The last-modified date-time of this module,
represented in RCS format (text C<Date:> with date and time, 
enclosed by C<$>s).

=item Module/Require (0 - infinite)

A list of modules (DOM modules or other liburary modules)
that is required by entire module.

=back

=cut

## Get general information
$Info->{source_filename} = $ARGV;

## Initial Namespace bindings
for ([ManakaiDOM => ExpandedURI q<ManakaiDOM:>],
     [http => q<http:>]) {
  $Info->{Namespace}->{$_->[0]} = $_->[1];
}

## Initial DataType aliasing and inheritance
for (ExpandedURI q<ManakaiDOM:ManakaiDOMURI>,
     ExpandedURI q<ManakaiDOM:ManakaiDOMNamespaceURI>,
     ExpandedURI q<ManakaiDOM:ManakaiDOMFeatureName>,
     ExpandedURI q<ManakaiDOM:ManakaiDOMFeatureVersion>,
     ExpandedURI q<ManakaiDOM:ManakaiDOMFeatures>) {
  $Info->{DataTypeAlias}->{$_}
       ->{isa_uri} = [ExpandedURI q<DOMMain:DOMString>];
}

register_namespace_declaration ($source);

my $Module = $source->get_attribute ('Module', make_new_node => 1);
$Info->{Name} = perl_name $Module->get_attribute_value ('Name'), ucfirst => 1
  or valid_err q<Module name (/Module/Name) MUST be specified>;
$Info->{Namespace}->{(DEFAULT_PFX)}
  = $Module->get_attribute_value ('Namespace')
  or valid_err q<Module namespace URI (/Module/Namespace) MUST be specified>;
$Info->{Namespace}->{$Module->get_attribute_value ('Name')}
  = $Info->{Namespace}->{(DEFAULT_PFX)};
my $pack_node = get_perl_definition_node $Module, name => 'BindingName';
if ($pack_node) {
  $Info->{Package} = perl_code $pack_node->value;
} else {
  $Info->{Package} = perl_package_name name => $Info->{Name};
}
$Info->{uri_to_perl_package}->{$Info->{Namespace}->{(DEFAULT_PFX)}}
  = $Info->{Package};
$Info->{Require_perl_package} = {};
$Info->{Require_perl_package_use} = {};

## Make source code
$result .= perl_comment q<This file is automatically generated from> . "\n" .
                        q<"> . $Info->{source_filename} . q<" at > .
                        rfc3339_date (time) . qq<.\n> .
                        q<Don't edit by hand!>;

$result .= perl_statement q<use strict>;

local $Status->{depth} = $Status->{depth} + 1;
$result .= perl_package full_name => $Info->{Package};
$result .= perl_statement perl_assign 'our $VERSION' => version_date time;

$result .= pod_block
             pod_head (1, 'NAME'),
             pod_para ($Info->{Package} .
                       ' - ' . get_description ($Module, name => 'FullName')),
             section (
               opt => pod_head (1, 'DESCRIPTION'),
               req => pod_para (get_description ($Module)),
             ),
             pod_head (1, 'DOM INTERFACES');

## Conditions
  my $defcond = 0;
  for my $cond (@{$Module->child_nodes}) {
    next unless $cond->node_type eq '#element' and
                $cond->local_name eq 'ConditionDef';
    my $name = $cond->get_attribute_value ('Name', default => '');
    my $isa = $cond->get_attribute_value ('ISA', default => []);
    my $fullname = get_description $cond, name => 'FullName';
    $isa = [$isa] unless ref $isa;
    if ($name =~ /^DOM(\d+)$/) {
      $defcond = $1 if $1 > $defcond;
      $fullname ||= "DOM Level " . (0 + $1);
    }
    $Info->{Condition}->{$name}->{ISA} = $isa;
    $Info->{Condition}->{$name}->{FullName} = $fullname || $name;
  }
  if (keys %{$Info->{Condition}}) {
    $Info->{NormalCondition} = $Module->get_attribute_value
                                            ('NormalCondition') ||
                                $defcond ? 'DOM' . $defcond :
                                valid_err q<Module/NormalCondition required>;
  }

## 'require'ing external modules
{
  my $req = $Module->get_attribute ('Require', make_new_node => 1);
  my $reqModule = sub {
    my ($name, $me, $you) = @_;
    if ($you->get_attribute_value ('Name', default => '') eq $name) {
      return 1;
    } else {
      return 0;
    }
  };
  if (not $req->get_element_by (sub {$reqModule->('ManakaiDOMMain', @_)})) {
    for ($req->append_new_node (type => '#element',
                                local_name => 'Module')) {
      $_->set_attribute (Name => 'ManakaiDOMMain');
      $_->set_attribute (Namespace => ExpandedURI q<ManakaiDOM:>);
    }
  }
  if (not $req->get_element_by (sub {$reqModule->('DOMMain', @_)})) {
    for ($req->append_new_node (type => '#element',
                                local_name => 'Module')) {
      $_->set_attribute (Name => 'DOMMain');
      $_->set_attribute (Namespace => ExpandedURI q<DOMMain:>);
    }
  }
  $result .= req2perl $Module;
}

for my $node (@{$source->child_nodes}) {
  if ($node->node_type ne '#element') {
    ##
  } elsif ($node->local_name eq 'IF') {
    $result .= if2perl $node;
  } elsif ($node->local_name eq 'Exception' or
           $node->local_name eq 'Warning') {
    $result .= exception2perl $node;
  } elsif ($node->local_name eq 'DataType') {
    $result .= datatype2perl $node;
  } elsif ($node->local_name eq 'DataTypeAlias') {
    $result .= datatypealias2perl $node;
  } elsif ($node->local_name eq 'ConstGroup') {
    $result .= constgroup2perl $node;
  } elsif ($node->local_name eq 'Const') {
    $result .= const2perl $node;
  } elsif ({qw/Module 1 Namespace 1 ImplNote 1/}->{$node->local_name}) {
    #
  } else {
    valid_warn qq{Top-level element type "@{[$node->local_name]}" not supported};
  }
}

## Export
if (keys %{$Status->{EXPORT_OK}||{}}) {
  $result .= perl_package full_name => $Info->{Package};
  $result .= perl_statement 'require Exporter';
  $result .= perl_inherit ['Exporter'];
  $result .= perl_statement
               perl_assign
                    perl_var (type => '@', scope => 'our',
                              local_name => 'EXPORT_OK')
                 => '(' . perl_list (keys %{$Status->{EXPORT_OK}}) . ')';
  if (keys %{$Status->{EXPORT_TAGS}||{}}) {
    $result .= perl_statement
                 perl_assign
                       perl_var (type => '%', scope => 'our',
                                 local_name => 'EXPORT_TAGS')
                   => '(' . perl_list (map {
                         $_ => [keys %{$Status->{EXPORT_TAGS}->{$_}}]
                      } keys %{$Status->{EXPORT_TAGS}}) . ')';
  }
}

## Feature
my @feature_desc;
my $features = 0;
for my $condition (sort keys %{$Info->{Condition}}, '') {
  for my $Feature (@{$Module->child_nodes}) {
    next unless $Feature->node_type eq '#element' and
                $Feature->local_name eq 'Feature' and
                condition_match $Feature, condition => $condition;
    is_all_implemented condition => $condition,
                       not_implemented => (my $not_implemented = []);
    
    my $f_name = $Feature->get_attribute_value ('Name', default => '');
    unless (length $f_name) {
      $f_name = expanded_uri $Feature->get_attribute_value ('QName');
    }
    my $f_ver = $Feature->get_attribute_value ('Version');
    
    push @feature_desc, pod_item ('Feature ' . pod_code ($f_name) .
                                  ' version ' . pod_code ($f_ver) .
                                  ($Info->{Condition}->{$condition}->{FullName} ?
                                  ' [' . $Info->{Condition}->{$condition}
                                              ->{FullName} . ']' : '')),
                        pod_paras (get_description $Feature);

    if (@$not_implemented) {
      push @feature_desc, pod_para ('This module provides interfaces '.
                                    'of this feature but not yet fully ' .
                                    'implemented.');
      $result .= perl_comment "$f_name, $f_ver: $not_implemented->[0]." .
                              "$not_implemented->[1]<$not_implemented->[2]>" .
                              " not implemented.";
    } else {
      push @feature_desc, pod_para ('This module implements this feature, ' .
                                    'so that the method calls such as ' .
                                    pod_code ('$DOMImplementation' .
                                              '->hasFeature (' .
                                              perl_literal ($f_name) .
                                              ', ' . perl_literal ($f_ver) .
                                              ')') . ' or ' .
                                    pod_code ('$DOMImplementation' .
                                              '->hasFeature (' .
                                              perl_literal ($f_name) .
                                              ', null)') .
                                    ' will return ' . pod_code ('true') . '.');
    }

    for (@{$Feature->child_nodes}) {
      next unless $_->node_type eq '#element';
      if ($_->local_name eq 'Contrib') {
        my $n = $_->value;
        my $ccondition;
        if ($n =~ s/::([^:]*)$//) {
          $ccondition = $1;
        }
        if ($n =~ s/^[^:]*://) {
          # currently prefix is not used
        }
        $result .= perl_statement
                   perl_assign
                     perl_var (type => '$',
                               package => {
                                 name => $n,
                                 condition => $ccondition,
                                 is_internal => 1,
                               },
                               local_name => 'Feature').
                           ## Feature name is case-insensitive
                     '->{'.perl_literal (lc $f_name).'}->{'.
                     perl_literal (@$not_implemented ? '+dummy+' : $f_ver) . '}'
                     => 1;
      } elsif ({
                  qw/Name 1 QName 1 FullName 1 Version 1 
                     Description 1 ImplNote 1 Spec 1
                     Condition 1 /
               }->{$_->local_name}) {
      } else {
        valid_err q<Unknown element type>, node => $_;
      }
    }

    $features++;
  }
}
if (@feature_desc) {
  $result .= pod_block 
               pod_head (1, 'DOM FEATURE'.($features>1?'S':'')),
               pod_list 4, @feature_desc;
}

## TODO list
my @todo;
    ## From not-implemented list
    for my $if (sort keys %{$Info->{is_implemented}}) {
      for my $mem (sort keys %{$Info->{is_implemented}->{$if}}) {
        for my $cond (sort keys %{$Info->{is_implemented}->{$if}->{$mem}}) {
          if (not $Info->{is_implemented}->{$if}->{$mem}->{$cond}) {
            push @todo, pod_item ('Implement '.pod_code ($if).'.'.
                                  pod_code ($mem).'.'),
                        pod_para ('Condition = '.
                                  ($Info->{Condition}->{$cond}->{FullName} ||
                                   '(empty)'));
          }
        }
      }
    }
    ## From Description, ImplNote, Def
    my $a;
    $a = sub {
      my $n = shift;
      for (@{$n->child_nodes}) {
        if ($_->node_type eq '#element') {
          $a->($_);
        }
      }
      if (($n->node_type eq '#element' and
           {qw/Description 1 ImplNote 1
               Def 1 IntDef 1/}->{$n->local_name}) or
          $n->node_type eq '#comment') {
        my $v = $n->value;
        if (defined $v) {
          if (ref $v eq 'ARRAY') {
            $v = join "\n", @$v;
          }
          if ($v =~ /\b(TODO|ISSUE|BUG):/) {
            push @todo, pod_item ($1.': '.pod_code $n->node_path(key => 'Name'));
            my $t = $n->node_type eq '#comment' ? ExpandedURI q<DOMMain:any> :
                    $n->get_attribute_value
                           ('Type',
                            default => {
                              Description => ExpandedURI q<lang:disdoc>,
                              ImplNote => ExpandedURI q<lang:disdoc>,
                              Def => ExpandedURI q<DOMMain:any>,
                              IntDef => ExpandedURI q<DOMMain:any>,
                            }->{$n->local_name});
            if ($t eq ExpandedURI q<lang:disdoc>) {
              push @todo, disdoc2pod $v;
            } else {
              push @todo, pod_pre ($v);
            }
          }
        }
      }
    };
  $a->($source);
  if (@todo) {
    $result .= pod_block
                 pod_head (1, 'TO DO'),
                 pod_list 4, @todo;
  }


## Namespace bindings for documentation
if (my $n = keys %{$Status->{ns_in_doc}}) {
  my @desc = (pod_head (1, 'NAMESPACE BINDING'.($n > 1 ? 'S' : '')),
              pod_para ('In this documentation, namespace prefix'.
                        ($n > 1 ? 'es ' : ' ').
                        ($n > 1 ? 'are' : 'is').' bound to:'));
  push @desc,
    pod_list 4, map {
      pod_item (pod_code $_),
      pod_para (pod_code ($Status->{ns_in_doc}->{$_})),
    } keys %{$Status->{ns_in_doc}};
  $result .= pod_block @desc;
}

## See also
  ## TODO: implement this.

## Author
my @desc;
my @author;
my $author;
my $authors = 0;
for (@{$Module->child_nodes}) {
  if ($_->node_type eq '#element' and $_->local_name eq 'Author') {
    my $n = get_description ($_, name => 'FullName');
    push @author, pod_item $n;
    my @d;
    $author = defined $author ? $authors ? $author
                                         : ($authors++, $author . ', et al.')
                              : $n;
    for (@{$_->child_nodes}) {
      next unless $_->node_type eq '#element';
      if ($_->local_name eq 'Mail') {
        push @d, pod_item ('Mail'), pod_para (pod_mail $_->value);
      } elsif ({qw/FullName 1/}->{$_->local_name}) {
        # 
      } else {
        valid_err q<Unknown element type>, node => $_;
      }
    }
    push @author, pod_list 6, @d if @d;
  }
}
$author = 'AUTHORS' unless defined $author;
if (@author) {
  push @desc, pod_head (1, 'AUTHOR'.($authors?'S':'')),
              pod_list (4, @author);
}

## License
push @desc, pod_head (1, 'LICENSE');
my $year = (gmtime)[5]+1900;
my $license = expanded_uri
                $Module->get_attribute_value ('License', default => '');
if ($license eq ExpandedURI q<license:Perl>) {
  push @desc, 
    pod_para (qq<Copyright $year $author.  All rights reserved.>),
    pod_para q<This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.>;
} elsif ($license eq ExpandedURI q<license:Perl+MPL>) {
  push @desc, 
    pod_para (qq<Copyright $year $author.  All rights reserved.>),
    pod_para (q<This program is free software; you can redistribute it and/or >.
             q<modify it under the same terms as Perl itself.>),

    pod_para (q<Alternatively, the contents of this file may be used >.
              q<under the following terms (the >.pod_dfn (q<MPL/GPL/LGPL>).
q<, in which case the provisions of the MPL/GPL/LGPL are applicable instead >.
q<of those above. If you wish to allow use of your version of this file only >.
q<under the terms of the MPL/GPL/LGPL, and not to allow others to >.
q<use your version of this file under the terms of the Perl, indicate your >.
q<decision by deleting the provisions above and replace them with the notice >.
q<and other provisions required by the MPL/GPL/LGPL. If you do not delete >.
q<the provisions above, a recipient may use your version of this file under >.
q<the terms of any one of the Perl or the MPL/GPL/LGPL. >),

    pod_head (2, 'MPL/GPL/LGPL'),

    # q<***** BEGIN LICENSE BLOCK *****>
    pod_para (q<Version: MPL 1.1/GPL 2.0/LGPL 2.1>),

    pod_para
(q<The contents of this file are subject to the Mozilla Public License Version >.
q<1.1 (the >.pod_dfn (q<License>).q<); you may not use this file except in >.
q<compliance with >.
q<the License. You may obtain a copy of the License at >.
pod_uri (q<http://www.mozilla.org/MPL/>).q<.>),

    pod_para
(q<Software distributed under the License is distributed on an ">.
pod_em (q<AS IS>).q<" basis, >.
pod_em (q<WITHOUT WARRANTY OF ANY KIND>).
q<, either express or implied. See the License >.
q<for the specific language governing rights and limitations under the >.
q<License. >);

  my $orig = $Module->get_attribute ('License')->get_attribute ('Original');
  if ($orig) {
    push @desc, pod_para ('The Original Code is the '.
                          get_description ($orig, name => 'FullName').'.');
    push @desc, pod_para ('The Initial Developer of the Original Code is '.
                          get_description ($orig->get_attribute ('Author'),
                                           name => 'FullName').'. '.
                          q<Portions created by the Initial Developer are >.
                          q<Copyright >.pod_char (name => 'copy').' '.
                          $orig->get_attribute_value ('Year',
                                                      default => $year).
                          q< the Initial Developer. All Rights Reserved.>);
  } else {
    my $a = $author;
    $a =~ /, et al\.$/ if $authors;

    push @desc, pod_para
      (q<The Original Code is the manakai DOM module.>),

      pod_para (qq<The Initial Developer of the Original Code is $a. >.
        q<Portions created by the Initial Developer are Copyright >.
        pod_char (name => 'copy').qq< $year >.
                ## ISSUE: Should first created year provided from some source?
        q<the Initial Developer. All Rights Reserved.>);
  }
  
  push @desc, pod_list 4,
                pod_item (q<Contributor(s):>),
                pod_para (q<See >.
                          pod_link (section => 'AUTHOR'.($authors?'S':'')).
                          q<.>);

  push @desc, pod_para
q<Alternatively, the contents of this file may be used under the terms of >.
q<either the GNU General Public License Version 2 or later (the ">.
pod_dfn (q<GPL>).q<"), or >.
q<the GNU Lesser General Public License Version 2.1 or later (the ">.
pod_dfn (q<LGPL>).q<"), >.
q<in which case the provisions of the GPL or the LGPL are applicable instead >.
q<of those above. If you wish to allow use of your version of this file only >.
q<under the terms of either the GPL or the LGPL, and not to allow others to >.
q<use your version of this file under the terms of the MPL, indicate your >.
q<decision by deleting the provisions above and replace them with the notice >.
q<and other provisions required by the GPL or the LGPL. If you do not delete >.
q<the provisions above, a recipient may use your version of this file under >.
q<the terms of any one of the MPL, the GPL or the LGPL. >;
  
  # ***** END LICENSE BLOCK *****
} elsif ($license) {
  valid_warn q<Unknown license: <$license>>;
  push @desc,
    pod_para (qq<Copyright $year $author.  All rights reserved.>),
    pod_para (qq<License: >.pod_uri ($license).q<.>);
} else {
  valid_err q<Required attribute "/Module/License" not specified>;
}
$result .= pod_block @desc;
             

$result .= perl_statement 1;

output_result $result;


__END__

=head1 SEE ALSO

W3C DOM Specifications <http://www.w3.org/DOM/DOMTR>

SuikaWiki:DOM <http://suika.fam.cx/~wakaba/-temp/wiki/wiki?DOM>

C<idl2dis.pl>: This script generates "dis" files,
that can be used as a template for the DOM implementation,
from DOM IDL files.

=head1 LICENSE

Copyright 2004 Wakaba <w@suika.fam.cx>.  All rights reserved.

This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.

Note that copyright holder(s) of this script does not claim 
any rights for materials outputed by this script, although it will
contain some fragments from this script.  License terms for them should be 
defined by the copyright holder of the source document.

=cut

# $Date: 2004/10/10 00:01:08 $