README
1NAME
2 Data::Inherited - Hierarchy-wide accumulation of list and hash results
3
4VERSION
5 version 1.100860
6
7SYNOPSIS
8 package Foo;
9 use base 'Data::Inherited';
10 use constant PROPERTIES => (qw/name address/);
11
12 package Bar;
13 use base 'Foo';
14 use constant PROPERTIES => (qw/age/);
15
16 package main;
17 my $bar = Bar->new;
18 print "$_\n" for $bar->every_list('PROPERTIES');
19
20 # prints:
21 #
22 # name
23 # address
24 # age
25
26DESCRIPTION
27 This is a mixin class. By inheriting from it you get two methods that
28 are able to accumulate hierarchy-wide list and hash results.
29
30METHODS
31 every_list(String $method_name, Bool ?$override_cache = 0)
32 Takes as arguments a method name (mandatory) and a boolean indicating
33 whether to override the cache (optional, off by default)
34
35 Causes every method in the object's hierarchy with the given name to be
36 invoked. The resulting list is the combined set of results from all the
37 methods, pushed together in top-to-bottom order (hierarchy-wise).
38
39 "every_list()" returns a list in list context and an array reference in
40 scalar context.
41
42 The result is cached (per calling package) and the next time the method
43 is called from the same package with the same method argument, the
44 cached result is returned. This is to speed up method calls, because
45 internally this module uses NEXT, which is quite slow. It is expected
46 that "every_list()" is used for methods returning static lists (object
47 defaults, static class definitions and such). If you want to override
48 the caching mechanism, you can provide the optional second argument. The
49 result is cached in any case.
50
51 See the synopsis for an example.
52
53 every_hash(String $method_name, Bool ?$override_cache = 0)
54 Takes as arguments a method name (mandatory) and a boolean indicating
55 whether to override the cache (optional, off by default)
56
57 Causes every method in the object's hierarchy with the given name to be
58 invoked. The resulting hash is the combined set of results from all the
59 methods, overlaid in top-to-bottom order (hierarchy-wise).
60
61 "every_hash()" returns a hash in list context and a hash reference in
62 scalar context.
63
64 The cache and the optional cache override argument work like with
65 "every_list()".
66
67 Example:
68
69 package Person;
70 use base 'Data::Inherited';
71
72 sub new {
73 my $class = shift;
74 my $self = bless {}, $class;
75 my %args = @_;
76 %args = ($self->every_hash('DEFAULTS'), %args);
77 $self->$_($args{$_}) for keys %args;
78 $self;
79 };
80
81 sub DEFAULTS {
82 first_name => 'John',
83 last_name => 'Smith',
84 };
85
86 package Employee;
87 use base 'Person';
88
89 sub DEFAULTS {
90 salary => 10_000,
91 }
92
93 package LocatedEmployee;
94 use base 'Employee';
95
96 # Note: no default for address, but different salary
97
98 sub DEFAULTS {
99 salary => 20_000,
100 first_name => 'Johan',
101 }
102
103 package main;
104 my $p = LocatedEmployee->new;
105
106 # salary: 20000
107 # first_name: Johan
108 # last_name: Smith
109
110 flush_every_cache_by_key(String $key)
111 Deletes the cache entry for the given key.
112
113INSTALLATION
114 See perlmodinstall for information and options on installing Perl
115 modules.
116
117BUGS AND LIMITATIONS
118 No bugs have been reported.
119
120 Please report any bugs or feature requests through the web interface at
121 <http://rt.cpan.org/Public/Dist/Display.html?Name=Data-Inherited>.
122
123AVAILABILITY
124 The latest version of this module is available from the Comprehensive
125 Perl Archive Network (CPAN). Visit <http://www.perl.com/CPAN/> to find a
126 CPAN site near you, or see
127 <http://search.cpan.org/dist/Data-Inherited/>.
128
129 The development version lives at
130 <http://github.com/hanekomu/Data-Inherited/>. Instead of sending
131 patches, please fork this project using the standard git and github
132 infrastructure.
133
134AUTHOR
135 Marcel Gruenauer <marcel@cpan.org>
136
137COPYRIGHT AND LICENSE
138 This software is copyright (c) 2004 by Marcel Gruenauer.
139
140 This is free software; you can redistribute it and/or modify it under
141 the same terms as the Perl 5 programming language system itself.
142
143