HTML::Strip - Perl extension for stripping HTML markup from text.


HTML-Strip documentation Contained in the HTML-Strip distribution.

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NAME

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HTML::Strip - Perl extension for stripping HTML markup from text.

SYNOPSIS

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  use HTML::Strip;

  my $hs = HTML::Strip->new();

  my $clean_text = $hs->parse( $raw_html );
  $hs->eof;

DESCRIPTION

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This module simply strips HTML-like markup from text in a very quick and brutal manner. It could quite easily be used to strip XML or SGML from text as well; but removing HTML markup is a much more common problem, hence this module lives in the HTML:: namespace.

It is written in XS, and thus about five times quicker than using regular expressions for the same task.

It does not do any syntax checking (if you want that, use HTML::Parser), instead it merely applies the following rules:

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Anything that looks like a tag, or group of tags will be replaced with a single space character. Tags are considered to be anything that starts with a < and ends with a >; with the caveat that a > character may appear in either of the following without ending the tag:

Quote

Quotes are considered to start with either a ' or a " character, and end with a matching character not preceded by an even number or escaping slashes (i.e. \" does not end the quote but \\\\" does).

Comment

If the tag starts with an exclamation mark, it is assumed to be a declaration or a comment. Within such tags, > characters do not end the tag if they appear within pairs of double dashes (e.g. <!-- <a href="old.htm">old page</a> --> would be stripped completely).

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Anything the appears within so-called strip tags is stripped as well. By default, these tags are title, script, style and applet.

HTML::Strip maintains state between calls, so you can parse a document in chunks should you wish. If one chunk ends half-way through a tag, quote, comment, or whatever; it will remember this, and expect the next call to parse to start with the remains of said tag.

If this is not going to be the case, be sure to call $hs->eof() between calls to $hs->parse().

METHODS

Constructor. Can optionally take a hash of settings (with keys corresponsing to the set_ methods below).

For example, the following is a valid constructor:

 my $hs = HTML::Strip->new(
                           striptags   => [ 'script', 'iframe' ],
                           emit_spaces => 0
                          );

Takes a string as an argument, returns it stripped of HTML.

Resets the current state information, ready to parse a new block of HTML.

Clears the current set of strip tags.

Adds the string passed as an argument to the current set of strip tags.

Takes a reference to an array of strings, which replace the current set of strip tags.

Takes a boolean value. If set to false, HTML::Strip will not attempt any conversion of tags into spaces. Set to true by default.

Takes a boolean value. If set to false, HTML::Strip will decode HTML entities. Set to true by default.

LIMITATIONS

Whitespace

Despite only outputting one space character per group of tags, and avoiding doing so when tags are bordered by spaces or the start or end of strings, HTML::Strip can often output more than desired; such as with the following HTML:

 <h1> HTML::Strip </h1> <p> <em> <strong> fast, and brutal </strong> </em> </p>

Which gives the following output:

 HTML::Strip    fast, and brutal   

Thus, you may want to post-filter the output of HTML::Strip to remove excess whitespace (for example, using tr/ / /s;). (This has been improved since previous releases, but is still an issue)

HTML Entities

HTML::Strip will only attempt decoding of HTML entities if HTML::Entities is installed.

EXPORT

None by default.

AUTHOR

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Alex Bowley <kilinrax@cpan.org>

SEE ALSO

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perl, HTML::Parser, HTML::Entities


HTML-Strip documentation Contained in the HTML-Strip distribution.

package HTML::Strip;

use 5.006;
use warnings;
use strict;

use Carp qw( carp croak );

require Exporter;
require DynaLoader;

our @ISA = qw(Exporter DynaLoader);

# Items to export into callers namespace by default. Note: do not export
# names by default without a very good reason. Use EXPORT_OK instead.
# Do not simply export all your public functions/methods/constants.

# This allows declaration	use HTML::Strip ':all';
# If you do not need this, moving things directly into @EXPORT or @EXPORT_OK
# will save memory.
our %EXPORT_TAGS = ( 'all' => [ qw(
                                  ) ] );

our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );

our @EXPORT = qw();

our $VERSION = '1.06';

bootstrap HTML::Strip $VERSION;

# Preloaded methods go here.

my $_html_entities_p = eval 'require HTML::Entities';

my %defaults = (
                striptags	=> [qw( title
                                        style
                                        script
                                        applet )],
                emit_spaces	=> 1,
                decode_entities	=> 1,
               );

sub new {
  my $class = shift;
  my $obj = create();
  bless $obj, $class;

  my %args = (%defaults, @_);
  while( my ($key, $value) = each %args ) {
    my $method = "set_${key}";
    if( $obj->can($method) ) {
      $obj->$method($value);
    } else {
      carp "Invalid setting '$key'";
    }
  }
  return $obj;
}

sub set_striptags {
  my ($self, @tags) = @_;
  if( ref($tags[0]) eq 'ARRAY' ) {
    $self->set_striptags_ref( $tags[0] );
  } else {
    $self->set_striptags_ref( \@tags );
  }
}

sub parse {
  my ($self, $text) = @_;
  my $stripped = $self->strip_html( $text );
  if( $self->decode_entities && $_html_entities_p ) {
    $stripped = HTML::Entities::decode($stripped);
  }
  return $stripped;
}

sub eof {
  my $self = shift;
  $self->reset();
}

1;
__END__
# Below is stub documentation for your module. You better edit it!