NAME

Data::Visitor::Lite - an easy implementation of Data::Visitor::Callback

SYNOPSIS

            

              
              
use Data::Visitor::Lite;
my $visitor = Data::Visitor::Lite->new(@replacers);
my $value = $visitor->visit({ 
  # some structure
});
            
          

DESCRIPTION

Data::Visitor::Lite is an easy implementation of Data::Visitor::Callback

new(@replacers)

this is a constructor of Data::Visitor::Lite.

            

              
              
my $visitor = Data::Visitor::Lite->new(
    [   -implements => ['to_plain_object'] =>
            sub { $_[0]->to_plain_object }
    ],
    [ -instance => 'Some::SuperClass' => sub { $_[0]->encode_to_utf8 } ]
    [ $replacer_type => $converter ]
);
#or
my $visitor2 = Data::Visitor::Lite->new(sub{
    # callback all node of the structure
});
my $value = $visitor->visit({ something });
            
          

replacer type

Data::Visitor::Lite has many expressions to make replacer which is applied only specified data type.

-implements

If you want to convert only the objects that implements 'to_plain_object', you can write just following :

            

              
              
my $visitor = Data::Visitor::Lite->new(
    [   -implements => ['to_plain_object'] => sub {
            return $_[0]->to_plain_object;
            }
    ]
);
            
          

it means it is easy to convert structures using duck typing.

-instance

"-instance" replacer type is able to create a converter for all instances of some class in the recursive structure.

            

              
              
my $visitor = Data::Visitor::Lite->new(
    [ -instance => 'Person' => sub{ $_[0]->nickname }]
);
$visitor->visit({
    master => Employer->new({ nickname => 'Kenji'}),
    slave  => Employee->new({ nickname => 'Daichi'});
});
# { master => "Kenji", slave => 'Daichi'}
            
          

-value

"-value" means not a reference and/or blessed object.

-hashkey

"-hashkey" means key string of the hash reference in the structure.

-string

"-string" means hash keys and all string value in the structure.

-object

"-object" means a reference and/or blessed object

other types

the origin of other replace types is Data::Util.( e.g. glob_ref , scalar_ref, invocant , number ,integer and so on )

AUTHOR

Daichi Hiroki <hirokidaichi {at} gmail.com>

SEE ALSO

Data::Visitor::Callback Data::Util

LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

cpanm Data::Visitor::Lite

perl -MCPAN -e shell
install Data::Visitor::Lite