.\" Automatically generated by Pod::Man 4.11 (Pod::Simple 3.35)
.\"
.\" Standard preamble:
.\" ========================================================================
.de Sp \" Vertical space (when we can't use .PP)
.if t .sp .5v
.if n .sp
..
.de Vb \" Begin verbatim text
.ft CW
.nf
.ne \\$1
..
.de Ve \" End verbatim text
.ft R
.fi
..
.\" Set up some character translations and predefined strings.  \*(-- will
.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
.\" double quote, and \*(R" will give a right double quote.  \*(C+ will
.\" give a nicer C++.  Capital omega is used to do unbreakable dashes and
.\" therefore won't be available.  \*(C` and \*(C' expand to `' in nroff,
.\" nothing in troff, for use with C<>.
.tr \(*W-
.ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
.ie n \{\
.    ds -- \(*W-
.    ds PI pi
.    if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
.    if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\"  diablo 12 pitch
.    ds L" ""
.    ds R" ""
.    ds C` ""
.    ds C' ""
'br\}
.el\{\
.    ds -- \|\(em\|
.    ds PI \(*p
.    ds L" ``
.    ds R" ''
.    ds C`
.    ds C'
'br\}
.\"
.\" Escape single quotes in literal strings from groff's Unicode transform.
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\"
.\" If the F register is >0, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD.  Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
.\"
.\" Avoid warning from groff about undefined register 'F'.
.de IX
..
.nr rF 0
.if \n(.g .if rF .nr rF 1
.if (\n(rF:(\n(.g==0)) \{\
.    if \nF \{\
.        de IX
.        tm Index:\\$1\t\\n%\t"\\$2"
..
.        if !\nF==2 \{\
.            nr % 0
.            nr F 2
.        \}
.    \}
.\}
.rr rF
.\" ========================================================================
.\"
.IX Title "HTML::Filter 3"
.TH HTML::Filter 3 "2021-03-04" "perl v5.26.3" "User Contributed Perl Documentation"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH "NAME"
HTML::Filter \- Filter HTML text through the parser
.SH "NOTE"
.IX Header "NOTE"
\&\fBThis module is deprecated.\fR The \f(CW\*(C`HTML::Parser\*(C'\fR now provides the
functionally of \f(CW\*(C`HTML::Filter\*(C'\fR much more efficiently with the
\&\f(CW\*(C`default\*(C'\fR handler.
.SH "SYNOPSIS"
.IX Header "SYNOPSIS"
.Vb 2
\& require HTML::Filter;
\& $p = HTML::Filter\->new\->parse_file("index.html");
.Ve
.SH "DESCRIPTION"
.IX Header "DESCRIPTION"
\&\f(CW\*(C`HTML::Filter\*(C'\fR is an \s-1HTML\s0 parser that by default prints the
original text of each \s-1HTML\s0 element (a slow version of \fBcat\fR\|(1) basically).
The callback methods may be overridden to modify the filtering for some
\&\s-1HTML\s0 elements and you can override \fBoutput()\fR method which is called to
print the \s-1HTML\s0 text.
.PP
\&\f(CW\*(C`HTML::Filter\*(C'\fR is a subclass of \f(CW\*(C`HTML::Parser\*(C'\fR. This means that
the document should be given to the parser by calling the \f(CW$p\fR\->\fBparse()\fR
or \f(CW$p\fR\->\fBparse_file()\fR methods.
.SH "EXAMPLES"
.IX Header "EXAMPLES"
The first example is a filter that will remove all comments from an
\&\s-1HTML\s0 file.  This is achieved by simply overriding the comment method
to do nothing.
.PP
.Vb 4
\&  package CommentStripper;
\&  require HTML::Filter;
\&  @ISA=qw(HTML::Filter);
\&  sub comment { }  # ignore comments
.Ve
.PP
The second example shows a filter that will remove any <\s-1TABLE\s0>s
found in the \s-1HTML\s0 file.  We specialize the \fBstart()\fR and \fBend()\fR methods
to count table tags and then make output not happen when inside a
table.
.PP
.Vb 9
\&  package TableStripper;
\&  require HTML::Filter;
\&  @ISA=qw(HTML::Filter);
\&  sub start
\&  {
\&     my $self = shift;
\&     $self\->{table_seen}++ if $_[0] eq "table";
\&     $self\->SUPER::start(@_);
\&  }
\&
\&  sub end
\&  {
\&     my $self = shift;
\&     $self\->SUPER::end(@_);
\&     $self\->{table_seen}\-\- if $_[0] eq "table";
\&  }
\&
\&  sub output
\&  {
\&      my $self = shift;
\&      unless ($self\->{table_seen}) {
\&          $self\->SUPER::output(@_);
\&      }
\&  }
.Ve
.PP
If you want to collect the parsed text internally you might want to do
something like this:
.PP
.Vb 5
\&  package FilterIntoString;
\&  require HTML::Filter;
\&  @ISA=qw(HTML::Filter);
\&  sub output { push(@{$_[0]\->{fhtml}}, $_[1]) }
\&  sub filtered_html { join("", @{$_[0]\->{fhtml}}) }
.Ve
.SH "SEE ALSO"
.IX Header "SEE ALSO"
HTML::Parser
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
Copyright 1997\-1999 Gisle Aas.
.PP
This library is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.