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XML/TokeParser version 0.05
=======================

INSTALLATION

To install this module type the following:

   perl Makefile.PL
   make
   make test
   make install


NAME
    XML::TokeParser - Simplified interface to XML::Parser

SYNOPSIS
        use XML::TokeParser;
                                                                        #
        #parse from file
        my $p = XML::TokeParser->new('file.xml')
                                                                        #
        #parse from open handle
        open IN, 'file.xml' or die $!;
        my $p = XML::TokeParser->new( \*IN, Noempty => 1 );
                                                                        #
        #parse literal text
        my $text = '<tag xmlns="http://www.omsdev.com">text</tag>';
        my $p    = XML::TokeParser->new( \$text, Namespaces => 1 );
                                                                        #
        #read next token
        my $token = $p->get_token();
                                                                        #
        #skip to <title> and read text
        $p->get_tag('title');
        $p->get_text();
                                                                        #
        #read text of next <para>, ignoring any internal markup
        $p->get_tag('para');
        $p->get_trimmed_text('/para');
                                                                        #
        #process <para> if interesting text
        $t = $p->get_tag('para');
        $p->begin_saving($t);
        if ( $p->get_trimmed_text('/para') =~ /interesting stuff/ ) {
            $p->restore_saved();
            process_para($p);
        }

DESCRIPTION
    XML::TokeParser provides a procedural ("pull mode") interface to
    XML::Parser in much the same way that Gisle Aas' HTML::TokeParser
    provides a procedural interface to HTML::Parser. XML::TokeParser splits
    its XML input up into "tokens," each corresponding to an XML::Parser
    event.

    A token is a bless'd reference to an array whose first element is an
    event-type string and whose last element is the literal text of the XML
    input that generated the event, with intermediate elements varying
    according to the event type.

    Each token is an *object* of type XML::TokeParser::Token. Read
    "XML::TokeParser::Token" to learn what methods are available for
    inspecting the token, and retrieving data from it.

METHODS
    $p = XML::TokeParser->new($input, [options])
        Creates a new parser, specifying the input source and any options.
        If $input is a string, it is the name of the file to parse. If
        $input is a reference to a string, that string is the actual text to
        parse. If $input is a reference to a typeglob or an IO::Handle
        object corresponding to an open file or socket, the text read from
        the handle will be parsed.

        Options are name=>value pairs and can be any of the following:

        Namespaces
            If set to a true value, namespace processing is enabled.

        ParseParamEnt
            This option is passed on to the underlying XML::Parser object;
            see that module's documentation for details.

        Noempty
            If set to a true value, text tokens consisting of only
            whitespace (such as those created by indentation and line breaks
            in between tags) will be ignored.

        Latin
            If set to a true value, all text other than the literal text
            elements of tokens will be translated into the ISO 8859-1
            (Latin-1) character encoding rather than the normal UTF-8
            encoding.

        Catalog
            The value is the URI of a catalog file used to resolve PUBLIC
            and SYSTEM identifiers. See XML::Catalog for details.

    $token = $p->get_token()
        Returns the next token, as an array reference, from the input.
        Returns undef if there are no remaining tokens.

    $p->unget_token($token,...)
        Pushes tokens back so they will be re-read. Useful if you've read
        one or more tokens too far. Correctly handles "partial" tokens
        returned by get_tag().

    $token = $p->get_tag( [$token] )
        If no argument given, skips tokens until the next start tag or end
        tag token. If an argument is given, skips tokens until the start tag
        or end tag (if the argument begins with '/') for the named element.
        The returned token does not include an event type code; its first
        element is the element name, prefixed by a '/' if the token is for
        an end tag.

    $text = $p->get_text( [$token] )
        If no argument given, returns the text at the current position, or
        an empty string if the next token is not a 'T' token. If an argument
        is given, gathers up all text between the current position and the
        specified start or end tag, stripping out any intervening tags (much
        like the way a typical Web browser deals with unknown tags).

    $text = $p->get_trimmed_text( [$token] )
        Like get_text(), but deletes any leading or trailing whitespaces and
        collapses multiple whitespace (including newlines) into single
        spaces.

    $p->begin_saving( [$token] )
        Causes subsequent calls to get_token(), get_tag(), get_text(), and
        get_trimmed_text() to save the returned tokens. In conjunction with
        restore_saved(), allows you to "back up" within a token stream. If
        an argument is supplied, it is placed at the beginning of the list
        of saved tokens (useful because you often won't know you want to
        begin saving until you've already read the first token you want
        saved).

    $p->restore_saved()
        Pushes all the tokens saved by begin_saving() back onto the token
        stream. Stops saving tokens. To cancel saving without backing up,
        call begin_saving() and restore_saved() in succession.

  XML::TokeParser::Token
    A token is a blessed array reference, that you acquire using
    "$p->get_token" or "$p->get_tag", and that might look like:

        ["S",  $tag, $attr, $attrseq, $raw]
        ["E",  $tag, $raw]
        ["T",  $text, $raw]
        ["C",  $text, $raw]
        ["PI", $target, $data, $raw]

    If you don't like remembering array indices (you're a real programmer),
    you may access the attributes of a token like:

    "$t->tag", "$t->attr", "$t->attrseq", "$t->raw", "$t->text",
    "$t->target", "$t->data".

    ****Please note that this may change in the future, where as there will
    be 4 token types, XML::TokeParser::Token::StartTag ....

    What kind of token is it?

    To find out, inspect your token using any of these is_* methods (1 ==
    true, 0 == false, d'oh):

    is_text
    is_comment
    is_pi which is short for is_process_instruction
    is_start_tag
    is_end_tag
    is_tag

    What's that token made of? To retrieve data from your token, use any of
    the following methods, depending on the kind of token you have:

    target
        only for process instructions

    data
        only for process instructions

    raw for all tokens

    attr
        only for start tags, returns a hashref ( "print "#link ",
        ""$t->attr""->{href}" ).

    my $attrseq = $t->attrseq
        only for start tags, returns an array ref of the keys found in
        "$t->attr" in the order they originally appeared in.

    my $tagname = $t->tag
        only for tags ( "print "opening ", ""$t->tag"" if
        ""$t->is_start_tag" ).

    my $text = $token->text
        only for tokens of type text and comment

    Here's more detailed info about the tokens.

    Start tag
        The token has five elements: 'S', the element's name, a reference to
        a hash of attribute values keyed by attribute names, a reference to
        an array of attribute names in the order in which they appeared in
        the tag, and the literal text.

    End tag
        The token has three elements: 'E', the element's name, and the
        literal text.

    Character data (text)
        The token has three elements: 'T', the parsed text, and the literal
        text. All contiguous runs of text are gathered into single tokens;
        there will never be two 'T' tokens in a row.

    Comment
        The token has three elements: 'C', the parsed text of the comment,
        and the literal text.

    Processing instruction
        The token has four elements: 'PI', the target, the data, and the
        literal text.

    The literal text includes any markup delimiters (pointy brackets,
    <![CDATA[, etc.), entity references, and numeric character references
    and is in the XML document's original character encoding. All other text
    is in UTF-8 (unless the Latin option is set, in which case it's in
    ISO-8859-1) regardless of the original encoding, and all entity and
    character references are expanded.

    If the Namespaces option is set, element and attribute names are
    prefixed by their (possibly empty) namespace URIs enclosed in curly
    brackets and xmlns:* attributes do not appear in 'S' tokens.

DIFFERENCES FROM HTML::TokeParser
    Uses a true XML parser rather than a modified HTML parser.

    Text and comment tokens include extracted text as well as literal text.

    PI tokens include target and data as well as literal text.

    No tokens for declarations.

    No "textify" hash.

    unget_token correctly handles partial tokens returned by get_tag().

    begin_saving() and restore_saved()

EXAMPLES
    Example:

        use XML::TokeParser;
        use strict;
                                                                                   #
        my $text = '<tag foo="bar" foy="floy"> some text <!--comment--></tag>';
        my $p    = XML::TokeParser->new( \$text );
                                                                                   #
        print $/;
                                                                                   #
        while( defined( my $t = $p->get_token() ) ){
            local $\="\n";
            print '         raw = ', $t->raw;
                                                                                   #
            if( $t->tag ){
                print '         tag = ', $t->tag;
                                                                                   #
                if( $t->is_start_tag ) {
                    print '        attr = ', join ',', %{$t->attr};
                    print '     attrseq = ', join ',', @{$t->attrseq};
                }
                                                                                   #
                print 'is_tag       ', $t->is_tag;
                print 'is_start_tag ', $t->is_start_tag;
                print 'is_end_tag   ', $t->is_end_tag;
            }
            elsif( $t->is_pi ){
                print '      target = ', $t->target;
                print '        data = ', $t->data;
                print 'is_pi        ', $t->is_pi;
            }
            else {
                print '        text = ', $t->text;
                print 'is_text      ', $t->is_text;
                print 'is_comment   ', $t->is_comment;
            }
                                                                                   #
            print $/;
        }
        __END__

    Output:

                 raw = <tag foo="bar" foy="floy">
                 tag = tag
                attr = foo,bar,foy,floy
             attrseq = foo,foy
        is_tag       1
        is_start_tag 1
        is_end_tag   0

                 raw =  some text 
                text =  some text 
        is_text      1
        is_comment   0

                 raw = <!--comment-->
                text = comment
        is_text      0
        is_comment   1

                 raw = </tag>
                 tag = tag
        is_tag       1
        is_start_tag 0
        is_end_tag   1

BUGS
    To report bugs, go to
    <http://rt.cpan.org/NoAuth/Bugs.html?Dist=XML-TokeParser> or send mail
    to <bug-XML-Tokeparser@rt.cpan.org>

AUTHOR
    Copyright (c) 2003 D.H. aka PodMaster (current maintainer). Copyright
    (c) 2001 Eric Bohlman (original author).

    All rights reserved. This program is free software; you can redistribute
    it and/or modify it under the same terms as Perl itself. If you don't
    know what this means, visit <http://perl.com/> or <http://cpan.org/>.

SEE ALSO
    HTML::TokeParser, XML::Parser, XML::Catalog, XML::Smart, XML::Twig.