1Sub::HandlesVia::HandleUrsLeirbrCaornyt:r:iCboudtee(d3S)Puebr:l:HDaoncdulmeesnVtiaat:i:oHnandlerLibrary::Code(3)
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NAME

6       Sub::HandlesVia::HandlerLibrary::Code - library of code-related methods
7

SYNOPSIS

9         package My::Class {
10           use Moo;
11           use Sub::HandlesVia;
12           use Types::Standard 'CodeRef';
13           has attr => (
14             is => 'rwp',
15             isa => CodeRef,
16             handles_via => 'Code',
17             handles => {
18               'my_execute' => 'execute',
19               'my_execute_list' => 'execute_list',
20               'my_execute_method' => 'execute_method',
21               'my_execute_method_list' => 'execute_method_list',
22               'my_execute_method_scalar' => 'execute_method_scalar',
23               'my_execute_method_void' => 'execute_method_void',
24               'my_execute_scalar' => 'execute_scalar',
25               'my_execute_void' => 'execute_void',
26             },
27           );
28         }
29

DESCRIPTION

31       This is a library of methods for Sub::HandlesVia.
32

DELEGATABLE METHODS

34   "execute( @args )"
35       Calls the coderef, passing it any arguments.
36
37         my $coderef = sub { 'code' };
38         my $object  = My::Class->new( attr => $coderef );
39
40         # Calls: $coderef->( 1, 2, 3 )
41         $object->my_execute( 1, 2, 3 );
42
43   "execute_list( @args )"
44       Calls the coderef, passing it any arguments, and forcing list context.
45       If called in scalar context, returns an arrayref.
46
47         my $context;
48         my $coderef = sub { $context = wantarray(); 'code' };
49         my $object  = My::Class->new( attr => $coderef );
50
51         # Calls: $coderef->( 1, 2, 3 )
52         my $result = $object->my_execute_list( 1, 2, 3 );
53
54         say Dumper( $result );  ## ==> [ 'code' ]
55         say $context;           ## ==> true
56
57   "execute_method( @args )"
58       Calls the coderef as if it were a method, passing any arguments.
59
60         my $coderef = sub { 'code' };
61         my $object  = My::Class->new( attr => $coderef );
62
63         # Calls: $coderef->( $object, 1, 2, 3 )
64         $object->my_execute_method( 1, 2, 3 );
65
66   "execute_method_list( @args )"
67       Calls the coderef as if it were a method, passing any arguments, and
68       forcing list context. If called in scalar context, returns an arrayref.
69
70         my $context;
71         my $coderef = sub { $context = wantarray(); 'code' };
72         my $object  = My::Class->new( attr => $coderef );
73
74         # Calls: $coderef->( $object, 1, 2, 3 )
75         my $result = $object->my_execute_method_list( 1, 2, 3 );
76
77         say Dumper( $result );  ## ==> [ 'code' ]
78         say $context;           ## ==> true
79
80   "execute_method_scalar( @args )"
81       Calls the coderef as if it were a method, passing any arguments, and
82       forcing scalar context.
83
84         my $context;
85         my $coderef = sub { $context = wantarray(); 'code' };
86         my $object  = My::Class->new( attr => $coderef );
87
88         # Calls: $coderef->( $object, 1, 2, 3 )
89         my $result = $object->my_execute_method_scalar( 1, 2, 3 );
90
91         say $result;  ## ==> 'code'
92         say $context; ## ==> false
93
94   "execute_method_void( @args )"
95       Calls the coderef as if it were a method, passing any arguments, and
96       forcing void context. Returns undef.
97
98         my $context;
99         my $coderef = sub { $context = wantarray(); 'code' };
100         my $object  = My::Class->new( attr => $coderef );
101
102         # Calls: $coderef->( $object, 1, 2, 3 )
103         my $result = $object->my_execute_method_void( 1, 2, 3 );
104
105         say $result;  ## ==> undef
106         say $context; ## ==> undef
107
108   "execute_scalar( @args )"
109       Calls the coderef, passing it any arguments, and forcing scalar
110       context.
111
112         my $context;
113         my $coderef = sub { $context = wantarray(); 'code' };
114         my $object  = My::Class->new( attr => $coderef );
115
116         # Calls: $coderef->( 1, 2, 3 )
117         my $result = $object->my_execute_scalar( 1, 2, 3 );
118
119         say $result;  ## ==> 'code'
120         say $context; ## ==> false
121
122   "execute_void( @args )"
123       Calls the coderef, passing it any arguments, and forcing void context.
124       Returns undef.
125
126         my $context;
127         my $coderef = sub { $context = wantarray(); 'code' };
128         my $object  = My::Class->new( attr => $coderef );
129
130         # Calls: $coderef->( 1, 2, 3 )
131         my $result = $object->my_execute_void( 1, 2, 3 );
132
133         say $result;  ## ==> undef
134         say $context; ## ==> undef
135

EXTENDED EXAMPLES

137   Using execute_method
138       The execute_method handler allows a class to effectively provide
139       certain methods which can be overridden by parameters in the
140       constructor.
141
142         use strict;
143         use warnings;
144         use Data::Dumper;
145
146         package My::Processor {
147           use Moo;
148           use Sub::HandlesVia;
149           use Types::Standard qw( Str CodeRef );
150
151           has name => (
152             is => 'ro',
153             isa => Str,
154             default => 'Main Process',
155           );
156
157           my $NULL_CODEREF = sub {};
158
159           has _debug => (
160             is => 'ro',
161             isa => CodeRef,
162             handles_via => 'Code',
163             handles => { debug => 'execute_method' },
164             default => sub { $NULL_CODEREF },
165             init_arg => 'debug',
166           );
167
168           sub _do_stuff {
169             my $self = shift;
170             $self->debug( 'continuing process' );
171             return;
172           }
173
174           sub run_process {
175             my $self = shift;
176             $self->debug( 'starting process' );
177             $self->_do_stuff;
178             $self->debug( 'ending process' );
179           }
180         }
181
182         my $p1 = My::Processor->new( name => 'First Process' );
183         $p1->run_process; # no output
184
185         my @got;
186         my $p2 = My::Processor->new(
187           name => 'Second Process',
188           debug => sub {
189             my ( $processor, $message ) = @_;
190             push @got, sprintf( '%s: %s', $processor->name, $message );
191           },
192         );
193         $p2->run_process; # logged output
194
195         my @expected = (
196           'Second Process: starting process',
197           'Second Process: continuing process',
198           'Second Process: ending process',
199         );
200         say Dumper( \@got ); ## ==> \@expected
201

BUGS

203       Please report any bugs to
204       <https://github.com/tobyink/p5-sub-handlesvia/issues>.
205

SEE ALSO

207       Sub::HandlesVia.
208

AUTHOR

210       Toby Inkster <tobyink@cpan.org>.
211

213       This software is copyright (c) 2020, 2022 by Toby Inkster.
214
215       This is free software; you can redistribute it and/or modify it under
216       the same terms as the Perl 5 programming language system itself.
217

DISCLAIMER OF WARRANTIES

219       THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
220       WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
221       MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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225perl v5.36.0                      2022-S1u2b-:1:7HandlesVia::HandlerLibrary::Code(3)
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