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NAME

Web::Scraper::Filter - Base class for Web::Scraper filters

SYNOPSIS

package Web::Scraper::Filter::YAML;
use base qw( Web::Scraper::Filter );
use YAML ();

sub filter {
    my($self, $value) = @_;
    YAML::Load($value);
}

1;

use Web::Scraper;

my $scraper = scraper {
    process ".yaml-code", data => [ 'TEXT', 'YAML' ];
};

DESCRIPTION

Web::Scraper::Filter is a base class for text filters in Web::Scraper. You can create your own text filter by subclassing this module.

There are two ways to create and use your custom filter. If you name your filter Web::Scraper::Filter::Something, you just call:

process $exp, $key => [ 'TEXT', 'Something' ];

If you declare your filter under your own namespace, like 'MyApp::Filter::Foo',

process $exp, $key => [ 'TEXT', '+MyApp::Filter::Foo' ];

You can also inline your filter function or regexp without creating a filter class:

process $exp, $key => [ 'TEXT', sub { s/foo/bar/ } ];

process $exp, $key => [ 'TEXT', qr/Price: (\d+)/ ];
process $exp, $key => [ 'TEXT', qr/(?<name>\w+): (?<value>\w+)/ ];

Note that this function munges $_ and returns the count of replacement. Filter code special cases if the return value of the callback is number and $_ value is updated.

You can, of course, stack filters like:

process $exp, $key => [ '@href', 'Foo', '+MyApp::Filter::Bar', \&baz ];

AUTHOR

Tatsuhiko Miyagawa