NAME

Data::Visitor::Callback - A Data::Visitor with callbacks.

SYNOPSIS

        use Data::Visitor::Callback;

        my $v = Data::Visitor::Callback->new(
                value => sub { ... },
                array => sub { ... },
        );

        $v->visit( $some_perl_value );

DESCRIPTION

This is a Data::Visitor subclass that lets you invoke callbacks instead of needing to subclass yourself.

METHODS

new %opts, %callbacks

Construct a new visitor.

The options supported are:

ignore_return_values

When this is true (off by default) the return values from the callbacks are ignored, thus disabling the fmapping behavior as documented in Data::Visitor.

This is useful when you want to modify $_ directly

CALLBACKS

Use these keys for the corresponding callbacks.

The callback is in the form:

        sub {
                my ( $visitor, $data ) = @_;

                # or you can use $_, it's aliased

                return $data; # or modified data
        }

Within the callback $_ is aliased to the data, and this is also passed in the parameter list.

visit

Called for all values

value

Called for non objects, non container (hash, array, glob or scalar ref) values.

ref_value

Called after value, for references to regexes, globs and code.

plain_value

Called after value for non references.

object

Called for blessed objects.

array

Called for array references.

hash

Called for hash references.

glob

Called for glob references.

scalar

Called for scalar references.

AUTHOR

Yuval Kogman <nothingmuch@woobling.org>

COPYRIGHT & LICENSE

        Copyright (c) 2006 Yuval Kogman. All rights reserved
        This program is free software; you can redistribute
        it and/or modify it under the same terms as Perl itself.