1MooseX::SetOnce(3)    User Contributed Perl Documentation   MooseX::SetOnce(3)
2
3
4

NAME

6       MooseX::SetOnce - write-once, read-many attributes for Moose
7

VERSION

9       version 0.200002
10

SYNOPSIS

12       Add the "SetOnce" trait to attributes:
13
14         package Class;
15         use Moose;
16         use MooseX::SetOnce;
17
18         has some_attr => (
19           is     => 'rw',
20           traits => [ qw(SetOnce) ],
21         );
22
23       ...and then you can only set them once:
24
25         my $object = Class->new;
26
27         $object->some_attr(10);  # works fine
28         $object->some_attr(20);  # throws an exception: it's already set!
29

DESCRIPTION

31       The 'SetOnce' attribute lets your class have attributes that are not
32       lazy and not set, but that cannot be altered once set.
33
34       The logic is very simple:  if you try to alter the value of an
35       attribute with the SetOnce trait, either by accessor or writer, and the
36       attribute has a value, it will throw an exception.
37
38       If the attribute has a clearer, you may clear the attribute and set it
39       again.
40

AUTHOR

42       Ricardo SIGNES <rjbs@cpan.org>
43
45       This software is copyright (c) 2013 by Ricardo SIGNES.
46
47       This is free software; you can redistribute it and/or modify it under
48       the same terms as the Perl 5 programming language system itself.
49
50
51
52perl v5.30.1                      2020-01-30                MooseX::SetOnce(3)
Impressum