1 package HTML::TokeParser;
3 require HTML::PullParser;
4 @ISA=qw(HTML::PullParser);
9 use HTML::Entities qw(decode_entities);
14 start => "'S',tagname,attr,attrseq,text",
15 end => "'E',tagname,text",
16 text => "'T',text,is_cdata",
17 process => "'PI',token0,text",
18 comment => "'C',text",
19 declaration => "'D',text",
21 # options that default on
31 my $type = (ref($_[0]) eq "SCALAR") ? "doc" : "file";
32 %cnf = ($type => $_[0]);
38 my $textify = delete $cnf{textify} || {img => "alt", applet => "alt"};
40 my $self = $class->SUPER::new(%cnf, %ARGS) || return undef;
42 $self->{textify} = $textify;
52 $token = $self->get_token || return undef;
53 my $type = shift @$token;
54 next unless $type eq "S" || $type eq "E";
55 substr($token->[0], 0, 0) = "/" if $type eq "E";
56 return $token unless @_;
58 return $token if $token->[0] eq $_;
65 my($self, $token) = @_;
66 my $tag = $token->[1];
67 return undef unless exists $self->{textify}{$tag};
69 my $alt = $self->{textify}{$tag};
72 $text = &$alt(@$token);
74 $text = $token->[2]{$alt || "alt"};
75 $text = "[\U$tag]" unless defined $text;
85 while (my $token = $self->get_token) {
86 my $type = $token->[0];
88 my $text = $token->[1];
89 decode_entities($text) unless $token->[2];
91 } elsif ($type =~ /^[SE]$/) {
92 my $tag = $token->[1];
94 if (defined(my $text = _textify($self, $token))) {
101 if (!@_ || grep $_ eq $tag, @_) {
102 $self->unget_token($token);
106 if $tag eq "br" || !$HTML::Tagset::isPhraseMarkup{$token->[1]};
116 my $text = $self->get_text(@_);
117 $text =~ s/^\s+//; $text =~ s/\s+$//; $text =~ s/\s+/ /g;
124 while (my $token = $self->get_token) {
125 my $type = $token->[0];
127 my $text = $token->[1];
128 decode_entities($text) unless $token->[2];
130 } elsif ($type =~ /^[SE]$/) {
131 my $tag = $token->[1];
133 if (defined(my $text = _textify($self, $token))) {
138 if (!$HTML::Tagset::isPhraseMarkup{$tag}) {
139 $self->unget_token($token);
142 push(@text, " ") if $tag eq "br";
145 my $text = join("", @text);
146 $text =~ s/^\s+//; $text =~ s/\s+$//; $text =~ s/\s+/ /g;
157 HTML::TokeParser - Alternative HTML::Parser interface
161 require HTML::TokeParser;
162 $p = HTML::TokeParser->new("index.html") ||
163 die "Can't open: $!";
164 $p->empty_element_tags(1); # configure its behaviour
166 while (my $token = $p->get_token) {
172 The C<HTML::TokeParser> is an alternative interface to the
173 C<HTML::Parser> class. It is an C<HTML::PullParser> subclass with a
174 predeclared set of token types. If you wish the tokens to be reported
175 differently you probably want to use the C<HTML::PullParser> directly.
177 The following methods are available:
181 =item $p = HTML::TokeParser->new( $filename, %opt );
183 =item $p = HTML::TokeParser->new( $filehandle, %opt );
185 =item $p = HTML::TokeParser->new( \$document, %opt );
187 The object constructor argument is either a file name, a file handle
188 object, or the complete document to be parsed. Extra options can be
189 provided as key/value pairs and are processed as documented by the base
192 If the argument is a plain scalar, then it is taken as the name of a
193 file to be opened and parsed. If the file can't be opened for
194 reading, then the constructor will return C<undef> and $! will tell
197 If the argument is a reference to a plain scalar, then this scalar is
198 taken to be the literal document to parse. The value of this
199 scalar should not be changed before all tokens have been extracted.
201 Otherwise the argument is taken to be some object that the
202 C<HTML::TokeParser> can read() from when it needs more data. Typically
203 it will be a filehandle of some kind. The stream will be read() until
206 A newly constructed C<HTML::TokeParser> differ from its base classes
207 by having the C<unbroken_text> attribute enabled by default. See
208 L<HTML::Parser> for a description of this and other attributes that
209 influence how the document is parsed. It is often a good idea to enable
210 C<empty_element_tags> behaviour.
212 Note that the parsing result will likely not be valid if raw undecoded
213 UTF-8 is used as a source. When parsing UTF-8 encoded files turn
216 open(my $fh, "<:utf8", "index.html") || die "Can't open 'index.html': $!";
217 my $p = HTML::TokeParser->new( $fh );
220 If a $filename is passed to the constructor the file will be opened in
221 raw mode and the parsing result will only be valid if its content is
222 Latin-1 or pure ASCII.
224 If parsing from an UTF-8 encoded string buffer decode it first:
226 utf8::decode($document);
227 my $p = HTML::TokeParser->new( \$document );
232 This method will return the next I<token> found in the HTML document,
233 or C<undef> at the end of the document. The token is returned as an
234 array reference. The first element of the array will be a string
235 denoting the type of this token: "S" for start tag, "E" for end tag,
236 "T" for text, "C" for comment, "D" for declaration, and "PI" for
237 process instructions. The rest of the token array depend on the type
240 ["S", $tag, $attr, $attrseq, $text]
242 ["T", $text, $is_data]
245 ["PI", $token0, $text]
247 where $attr is a hash reference, $attrseq is an array reference and
248 the rest are plain scalars. The L<HTML::Parser/Argspec> explains the
251 =item $p->unget_token( @tokens )
253 If you find you have read too many tokens you can push them back,
254 so that they are returned the next time $p->get_token is called.
258 =item $p->get_tag( @tags )
260 This method returns the next start or end tag (skipping any other
261 tokens), or C<undef> if there are no more tags in the document. If
262 one or more arguments are given, then we skip tokens until one of the
263 specified tag types is found. For example:
265 $p->get_tag("font", "/font");
267 will find the next start or end tag for a font-element.
269 The tag information is returned as an array reference in the same form
270 as for $p->get_token above, but the type code (first element) is
271 missing. A start tag will be returned like this:
273 [$tag, $attr, $attrseq, $text]
275 The tagname of end tags are prefixed with "/", i.e. end tag is
282 =item $p->get_text( @endtags )
284 This method returns all text found at the current position. It will
285 return a zero length string if the next token is not text. Any
286 entities will be converted to their corresponding character.
288 If one or more arguments are given, then we return all text occurring
289 before the first of the specified tags found. For example:
291 $p->get_text("p", "br");
293 will return the text up to either a paragraph of linebreak element.
295 The text might span tags that should be I<textified>. This is
296 controlled by the $p->{textify} attribute, which is a hash that
297 defines how certain tags can be treated as text. If the name of a
298 start tag matches a key in this hash then this tag is converted to
299 text. The hash value is used to specify which tag attribute to obtain
300 the text from. If this tag attribute is missing, then the upper case
301 name of the tag enclosed in brackets is returned, e.g. "[IMG]". The
302 hash value can also be a subroutine reference. In this case the
303 routine is called with the start tag token content as its argument and
304 the return value is treated as the text.
306 The default $p->{textify} value is:
308 {img => "alt", applet => "alt"}
310 This means that <IMG> and <APPLET> tags are treated as text, and that
311 the text to substitute can be found in the ALT attribute.
313 =item $p->get_trimmed_text
315 =item $p->get_trimmed_text( @endtags )
317 Same as $p->get_text above, but will collapse any sequences of white
318 space to a single space character. Leading and trailing white space is
323 This will return all text found at the current position ignoring any
324 phrasal-level tags. Text is extracted until the first non
325 phrasal-level tag. Textification of tags is the same as for
326 get_text(). This method will collapse white space in the same way as
327 get_trimmed_text() does.
329 The definition of <i>phrasal-level tags</i> is obtained from the
336 This example extracts all links from a document. It will print one
337 line for each link, containing the URL and the textual description
338 between the <A>...</A> tags:
340 use HTML::TokeParser;
341 $p = HTML::TokeParser->new(shift||"index.html");
343 while (my $token = $p->get_tag("a")) {
344 my $url = $token->[1]{href} || "-";
345 my $text = $p->get_trimmed_text("/a");
346 print "$url\t$text\n";
349 This example extract the <TITLE> from the document:
351 use HTML::TokeParser;
352 $p = HTML::TokeParser->new(shift||"index.html");
353 if ($p->get_tag("title")) {
354 my $title = $p->get_trimmed_text;
355 print "Title: $title\n";
360 L<HTML::PullParser>, L<HTML::Parser>
364 Copyright 1998-2005 Gisle Aas.
366 This library is free software; you can redistribute it and/or
367 modify it under the same terms as Perl itself.