oracular (3) HTML::Highlight.3pm.gz
NAME
HTML::Highlight - A module to highlight words or patterns in HTML documents
SYNOPSIS
use HTML::Highlight;
# create the highlighter object
my $hl = new HTML::Highlight (
words => [
'word',
'any',
'car',
'some phrase'
],
wildcards => [
undef,
'%',
'*',
undef
],
colors => [
'#FF0000',
'red',
'green',
'rgb(255, 0, 0)'
],
czech_language => 0,
debug => 0
);
# Remember that you don't need to specify your own colors.
# The default colors should be optimal.
# Now you can use the object to highlight patterns in a document
# by passing content of the document to its highlight() method.
# The highlighter object "remembers" its configuration.
my $highlighted_document = $hl->highlight($document);
MOTIVATION
This module was originaly created to work together with fulltext indexing module DBIx::TextIndex to
highlight search results.
A need for a highlighter that takes wildcard matches and HTML tags into account and supports czech
language (or other Slavic languages) was the motivation to create this module.
DESCRIPTION
This module provides Google-like highlighting of words or patterns in HTML documents. This feature is
typically used to highlight search results.
The construcutor:
my $hl = new HTML::Highlight (
words => [],
wildcards => [],
colors => [],
czech_language => 0,
debug => 0
);
This is a constructor of the highlighter object. It takes an array of even number of parameters.
The words parameter is a reference to an array of words to highlight.
The wildcards parameter is a reference to an array of wildcards, that are applied to corresponding
words in the words array.
A wildcard can be either undef or one of '%' or '*'.
The "%" character means "match any characters":
"%" applied to 'car' ==> matches "car", "cars", "careful", ...
The "*" character means "match also plural form of the word":
"*" applied to 'car' ==> matches only "car" or "cars"
An undefined wildcard means "match exactly the corresponding word":
undefined wildcard applied to 'car' ==> matches only "car"
The colors parameter is a reference to an array of CSS color identificators, that are used to
highlight the corresponding words in the words array.
Default Google-like colors are used if you don't specify your own colors. Number of colors can be
lower than number of words - in this case the colors are rotated and some of the words are therefore
highlighted using the same color.
The highlighter takes HTML tags into account and therefore does not "highlight" a word or a pattern
inside a tag.
A support for diacritics insenstive matching for ISO-8859-2 languages (for for example the czech
language) can be activated using the czech_language option. This feature requires a module CzFast
that is available on CPAN in a directory of author TRIPIE or at http://geocities.com/tripiecz/.
Your system's locales must be set correctly to use the czech_language feature.
highlight
my $hl_document = $hl->highlight($document);
The only parameter is a document in that you want to highlight the words that were passed to the
constructor of the highlighter object. The method returns a version of the document in which the
words are highlighted.
preview_context
my $sections = $hl->preview_context($document, $num);
This method takes two parameters. The first one is the document you want to scan for the words that
were passed to the constructor of the highlighter object. The second parameter is an optional integer
that specifies maximum number of characters in each of the context sections (see below). This
parameter defaults to 80 characters if it's not specified. Minimum allowed value of this parameter is
60.
The method returns a reference to an array of sections of the document in which the words that were
passed to the constructor appear. HTML tags are removed before the document is proccessed and are
not present in the output. This feature is typically used in search engines to preview a context in
which words from a search query appear in the resulting documents. The words are always in the
middle of each of the sections. The number of sections this method returns is equal to the number of
words passed to the constructor of the highlighter object. That means only the first occurrence of
each of the words is taken into account.
SUPPORT
No official support is provided, but I welcome any comments, patches and suggestions on my email.
BUGS
I am aware of no bugs.
AVAILABILITY
http://geocities.com/tripiecz/
AUTHOR
Tomas Styblo, tripie@cpan.org, CPAN-ID TRIPIE Prague, the Czech republic
LICENSE
HTML::Highlight - A module to highlight words or patterns in HTML documents
Copyright (C) 2000 Tomas Styblo (tripie@cpan.org)
This module is free software; you can redistribute it and/or modify it under the terms of either:
a) the GNU General Public License as published by the Free Software Foundation; either version 1, or (at
your option) any later version, or
b) the "Artistic License" which comes with this module.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See either the GNU General
Public License or the Artistic License for more details.
You should have received a copy of the Artistic License with this module, in the file Artistic. If not,
I'll be glad to provide one.
You should have received a copy of the GNU General Public License along with this program; if not, write
to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
SEE ALSO
perl(1).