NAME
Data::Inherited - Hierarchy-wide accumulation of list and hash results
SYNOPSIS
package Foo; use base 'Data::Inherited'; use constant PROPERTIES => (qw/name address/);
package Bar; use base 'Foo'; use constant PROPERTIES => (qw/age/);
package main; my $bar = Bar->new; print "$_\n" for $bar->every_list('PROPERTIES');
prints
name address age
DESCRIPTION
This is a mixin class. By inheriting from it you get two methods that are able to accumulate hierarchy-wide list and hash results.
METHODS
every_list(String $method_name, Bool ?$override_cache = 0)
Takes as arguments a method name (mandatory) and a boolean indicating whether to override the cache (optional, off by default)
Causes every method in the object's hierarchy with the given name to be invoked. The resulting list is the combined set of results from all the methods, pushed together in top-to-bottom order (hierarchy-wise).
every_list() returns a list in list context and an array reference in
scalar context.
The result is cached (per calling package) and the next time the method is
called from the same package with the same method argument, the cached result
is returned. This is to speed up method calls, because internally this module
uses NEXT, which is quite slow. It is expected that every_list() is used
for methods returning static lists (object defaults, static class definitions
and such). If you want to override the caching mechanism, you can provide the
optional second argument. The result is cached in any case.
See the synopsis for an example.
every_hash(String $method_name, Bool ?$override_cache = 0)
Takes as arguments a method name (mandatory) and a boolean indicating whether to override the cache (optional, off by default)
Causes every method in the object's hierarchy with the given name to be invoked. The resulting hash is the combined set of results from all the methods, overlaid in top-to-bottom order (hierarchy-wise).
every_hash() returns a hash in list context and a hash reference in scalar
context.
The cache and the optional cache override argument work like with
every_list().
Example:
package Person; use base 'Data::Inherited';
sub new { my $class = shift; my $self = bless {}, $class; my %args = @; %args = ($self->every_hash('DEFAULTS'), %args); $self->$($args{$_}) for keys %args; $self; };
sub DEFAULTS { first_name => 'John', last_name => 'Smith', };
package Employee; use base 'Person';
sub DEFAULTS { salary => 10_000, }
package LocatedEmployee; use base 'Employee';
Note: no default for address, but different salary
sub DEFAULTS { salary => 20_000, first_name => 'Johan', }
package main; my $p = LocatedEmployee->new;
salary: 20000
first_name: Johan
last_name: Smith
flush_every_cache_by_key(String $key)
Deletes the cache entry for the given key.
BUGS AND LIMITATIONS
No bugs have been reported.
Please report any bugs or feature requests through the web interface at http://rt.cpan.org.
INSTALLATION
See perlmodinstall for information and options on installing Perl modules.
AVAILABILITY
The latest version of this module is available from the Comprehensive Perl Archive Network (CPAN). Visit http://www.perl.com/CPAN/ to find a CPAN site near you. Or see http://search.cpan.org/dist/Data-Domain-URI/.
AUTHORS
Marcel Grünauer, <marcel@cpan.org>
COPYRIGHT AND LICENSE
Copyright 2004-2009 by the authors.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.