Manual Pages for UNIX Darwin command on man HTML::TokeParser
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Manual Pages for UNIX Darwin command on man HTML::TokeParser

HTML::TokeParser(3) User Contributed Perl Documentation HTML::TokeParser(3)

NAME

HTML::TokeParser - Alternative HTML::Parser interface

SYNOPSIS

require HTML::TokeParser;

$p = HTML::TokeParser->new("index.html") ||

die "Can't open: $!";

$p->emptyelementtags(1); # configure its behaviour

while (my $token = $p->gettoken) {

#...

}

DESCRIPTION

The "HTML::TokeParser" is an alternative interface to the

"HTML::Parser" class. It is an "HTML::PullParser" subclass with a predeclared set of token types. If you wish the tokens to be reported differently you probably want to use the "HTML::PullParser" directly. The following methods are available:

$p = HTML::TokeParser->new( $filename, %opt );

$p = HTML::TokeParser->new( $filehandle, %opt );

$p = HTML::TokeParser->new( \$document, %opt );

The object constructor argument is either a file name, a file handle object, or the complete document to be parsed. Extra options can be provided as key/value pairs and are processed as documented by the base classes. If the argument is a plain scalar, then it is taken as the name of a file to be opened and parsed. If the file can't be opened for

reading, then the constructor will return "undef" and $! will tell

you why it failed. If the argument is a reference to a plain scalar, then this scalar is taken to be the literal document to parse. The value of this scalar should not be changed before all tokens have been extracted. Otherwise the argument is taken to be some object that the

"HTML::TokeParser" can read() from when it needs more data.

Typically it will be a filehandle of some kind. The stream will be read() until EOF, but not closed.

A newly constructed "HTML::TokeParser" differ from its base classes

by having the "unbrokentext" attribute enabled by default. See HTML::Parser for a description of this and other attributes that influence how the document is parsed. It is often a good idea to enable "emptyelementtags" behaviour. Note that the parsing result will likely not be valid if raw

undecoded UTF-8 is used as a source. When parsing UTF-8 encoded

files turn on UTF-8 decoding:

open(my $fh, "<:utf8", "index.html") || die "Can't open 'index.html': $!";

my $p = HTML::TokeParser->new( $fh );

# ...

If a $filename is passed to the constructor the file will be opened

in raw mode and the parsing result will only be valid if its

content is Latin-1 or pure ASCII.

If parsing from an UTF-8 encoded string buffer decode it first:

utf8::decode($document);

my $p = HTML::TokeParser->new( \$document );

# ...

$p->gettoken

This method will return the next token found in the HTML document, or "undef" at the end of the document. The token is returned as an array reference. The first element of the array will be a string denoting the type of this token: "S" for start tag, "E" for end tag, "T" for text, "C" for comment, "D" for declaration, and "PI" for process instructions. The rest of the token array depend on the type like this:

["S", $tag, $attr, $attrseq, $text]

["E", $tag, $text]

["T", $text, $isdata]

["C", $text]

["D", $text]

["PI", $token0, $text]

where $attr is a hash reference, $attrseq is an array reference and

the rest are plain scalars. The "Argspec" in HTML::Parser explains the details.

$p->ungettoken( @tokens )

If you find you have read too many tokens you can push them back,

so that they are returned the next time $p->gettoken is called.

$p->gettag

$p->gettag( @tags )

This method returns the next start or end tag (skipping any other tokens), or "undef" if there are no more tags in the document. If one or more arguments are given, then we skip tokens until one of the specified tag types is found. For example:

$p->gettag("font", "/font");

will find the next start or end tag for a font-element.

The tag information is returned as an array reference in the same

form as for $p->gettoken above, but the type code (first element)

is missing. A start tag will be returned like this:

[$tag, $attr, $attrseq, $text]

The tagname of end tags are prefixed with "/", i.e. end tag is returned like this:

["/$tag", $text]

$p->gettext

$p->gettext( @endtags )

This method returns all text found at the current position. It will return a zero length string if the next token is not text. Any entities will be converted to their corresponding character. If one or more arguments are given, then we return all text occurring before the first of the specified tags found. For example:

$p->gettext("p", "br");

will return the text up to either a paragraph of linebreak element. The text might span tags that should be textified. This is

controlled by the $p->{textify} attribute, which is a hash that

defines how certain tags can be treated as text. If the name of a start tag matches a key in this hash then this tag is converted to text. The hash value is used to specify which tag attribute to obtain the text from. If this tag attribute is missing, then the upper case name of the tag enclosed in brackets is returned, e.g. "[IMG]". The hash value can also be a subroutine reference. In this case the routine is called with the start tag token content as its argument and the return value is treated as the text.

The default $p->{textify} value is:

{img => "alt", applet => "alt"} This means that and tags are treated as text, and that the text to substitute can be found in the ALT attribute.

$p->gettrimmedtext

$p->gettrimmedtext( @endtags )

Same as $p->gettext above, but will collapse any sequences of

white space to a single space character. Leading and trailing white space is removed.

$p->getphrase

This will return all text found at the current position ignoring

any phrasal-level tags. Text is extracted until the first non

phrasal-level tag. Textification of tags is the same as for

gettext(). This method will collapse white space in the same way as gettrimmedtext() does.

The definition of phrasal-level tags is obtained from the

HTML::Tagset module. EEXXAAMMPPLLEESS This example extracts all links from a document. It will print one line for each link, containing the URL and the textual description between the ... tags:

use HTML::TokeParser;

$p = HTML::TokeParser->new(shift||"index.html");

while (my $token = $p->gettag("a")) {

my $url = $token->[1]{href} || "-";

my $text = $p->gettrimmedtext("/a");

print "$url\t$text\n";

} This example extract the from the document: <H3> use HTML::TokeParser; </H3><H3> $p = HTML::TokeParser->new(shift||"index.html"); </H3><P> if ($p->gettag("title")) { </P><P> my $title = $p->gettrimmedtext; </P><P> print "Title: $title\n"; </P> } <H3>SEE ALSO</H3> HTML::PullParser, HTML::Parser COPYRIGHT<P> Copyright 1998-2005 Gisle Aas. </P> This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. <H3>perl v5.8.8 2006-04-26 HTML::TokeParser(3) </H3></P></pre></div><br></div><br><BR> <center> <a target="_top" href="https://www.mywebuniversity.com/contact.html"> <font size=-1 color=WHITE><B>Contact us<B></font></a>      <font size=-1 color=WHITE>|</font>      <a target="_top" href="https://www.mywebuniversity.com/contact.html"> <B><font size=-1 color=WHITE>About us</font></B></a>      <font size=-1 color=WHITE>|</font>      <a target="_top" href="https://www.mywebuniversity.com/contact.html"><font size=-1 color=WHITE>Term of use</font></a>      <font size=-1 color=WHITE>| </font>     <font size=-1 color=WHITE> <b>Copyright © 2000-2019 MyWebUniversity.com ™</b></font> </center> </body> </html>