NAME

What::HTML - An HTML Parser

SYNOPSIS

  use What::HTML;
  
  my $s = q<<!DOCTYPE html><html>...</html>>;
  # $doc = an empty DOM |Document| object
  my $on_error = sub {
    my $error_code = shift;
    warn $error_code, "\n";
  };
  
  What::HTML->parse_string ($s => $doc, $onerror);
  
  ## Then, |$doc| is the DOM representation of |$s|.

DESCRIPTION

The What::HTML module contains HTML parser and serializer.

The HTML parser can be used to construct the DOM tree representation from an HTML document. The parsing and tree construction are done as described in the Web Application 1.0 specification.

The HTML serializer can be used to obtain the HTML document representation of a DOM tree (or a tree fragment thereof). The serialization is performed as described in the Web Applications 1.0 specification for innerHTML DOM attribute.

This module is part of WHAT.pm - Perl Modules for Web Hypertext Application Technologies.

METHODS

[$doc =] What::HTML->parse_string ($s, $doc[, $onerror]);

Parse a string $s as an HTML document.

The first argument, $s, MUST be a string. It is parsed as a sequence of characters representing an HTML document.

The second argument, $doc, MUST be an empty read-write DOM Document object. The HTML DOM tree is constructed onto this Document object.

The third argument, $onerror, MUST be a reference to the error handler code. Whenever a parse error is detected, this code is invoked with an argument that contains a useless string that might describe what is wrong. The code MAY throw an exception, so that whole the parsing process aborts. Otherwise, the parser will continue to process the input. The code MUST NOT modify $s or $doc. If it does, then the result is undefined. This argument is optional; if missing, any parse error makes that string being warned.

The method returns the DOM Document object (i.e. the second argument).

Note that the What::NanoDOM module provides a non-conforming implementation of DOM that only implements the subset that is necessary for the purpose of What::HTML's parsing and serializing. With this module, creating a new HTML Document object from a string containing HTML document can be coded as:

  use What::HTML;
  use What::NanoDOM;
  my $doc = What::HTML->parse_string ($s => What::NanoDOM->new, $onerror);

$s = What::HTML->get_inner_html ($node[, $onerror]);

Return the HTML serialization of a DOM node $node.

The first argument, $node, MUST be a DOM Document, Node, or DocumentFragment object.

The second argument, $onerror, MUST be a reference to the error handling code. This code will be invoked if a descendant of $node is not of Element, Text, CDATASection, Comment, DocumentType, or EntityReference so that INVALID_STATE_ERR MUST be thrown. The code will be invoked with an argument, which is the node whose type is invalid. This argument is optional; if missing, any such node is simply ignored.

The method returns the inner_html attribute value, i.e. the HTML serialization of the $node.

TO DO

Tokenizer should emit a sequence of character tokens as one token to improve performance.

A method that accepts a byte stream as an input.

Charset detection algorithm.

Setting inner_html.

And there are many ``TODO''s and ``ISSUE''s in the source code.

AUTHOR

Wakaba <w@suika.fam.cx>.

LICENSE

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