1Declare::Constraints::SUismeprleC:o:nLtirbiDrbeaucrtlyea:dr:eBP:ae:srCelo(n3Ds)otcruamiennttsa:t:iSoinmple::Library::Base(3)
2
3
4
6 Declare::Constraints::Simple::Library::Base - Library Base Class
7
9 package My::Constraint::Library;
10 use warnings;
11 use strict;
12
13 # this installs the base class and helper functions
14 use Declare::Constraints::Simple-Library;
15
16 # we can also automagically provide other libraries
17 # to the importer
18 use base 'Declare::Constraints::Simple::Library::Numericals';
19
20 # with this we define a constraint to check a value
21 # against a serial number regular expression
22 constraint 'SomeSerial',
23 sub {
24 return sub {
25 return _true if $_[0] =~ /\d{3}-\d{3}-\d{4}/;
26 return _false('Not in SomeSerial format');
27 };
28 };
29
30 1;
31
33 This base class contains the common library functionalities. This
34 includes helper functions and install mechanisms.
35
37 install_into($target)
38 Installs the base classes and helper functions into the $target
39 namespace. The %CONSTRAINT_GENERATORS package variable of that class
40 will be used as storage for it's constraints.
41
42 fetch_constraint_declarations()
43 Class method. Returns all constraints registered to the class.
44
45 fetch_constraint_generator($name)
46 Class method. Returns the constraint generator code reference
47 registered under $name. The call will raise a "croak" if the generator
48 could not be found.
49
50 prepare_generator($constraint_name, $generator)
51 Class method. This wraps the $generator in a closure that provides
52 stack and failure-collapsing decisions.
53
54 add_constraint_generator($name, $code)
55 Class method. The actual registration method, used by "constraint".
56
58 Note that some of the helper functions are prefixed with "_". Although
59 this means they are internal functions, it is ok to call them, as they
60 have a fixed API. They are not distribution internal, but library
61 internal, and only intended to be used from inside constraints.
62
63 constraint($name, $code)
64 constraint 'Foo', sub { ... };
65
66 This registers a new constraint in the calling library. Note that
67 constraints have to return result objects. To do this, you can use the
68 helper functions "_result($bool, $msg", _true() and _false($msg).
69
70 _result($bool, $msg)
71 Returns a new result object. It's validity flag will depend on the
72 $bool argument. The $msg argument is the error message to use on
73 failure.
74
75 _false($msg)
76 Returns a non-valid result object, with it's message set to $msg.
77
78 _true()
79 Returns a valid result object.
80
81 _info($info)
82 Sets the current failure info to use in the stack info part.
83
84 _apply_checks($value, \@constraints, [$info])
85 This applies all constraints in the "\@constraints" array reference to
86 the passed $value. You can optionally specify an $info string to be
87 used in the stack of the newly created non-valid results.
88
89 _listify($value)
90 Puts $value into an array reference and returns it, if it isn't already
91 one.
92
93 _with_message($msg, $closure, @args)
94 This is the internal version of the general "Message" constraint. It
95 sets the current overriden message to $msg and executes the $closure
96 with @args as arguments.
97
98 _with_scope($scope_name, $constraint, @args)
99 Applies the $constraint to @args in a newly created scope named by
100 $scope_name.
101
102 _set_result($scope, $name, $result)
103 Stores the given $result unter the name $name in $scope.
104
105 _get_result($scope, $name)
106 Returns the result named $name from $scope.
107
108 _has_result($scope, $name)
109 Returns true only if such a result was registered already.
110
112 Declare::Constraints::Simple, Declare::Constraints::Simple::Library
113
115 Robert 'phaylon' Sedlacek "<phaylon@dunkelheit.at>"
116
118 This module is free software, you can redistribute it and/or modify it
119 under the same terms as perl itself.
120
121
122
123perl v5.30.0 De2c0l1a9r-e0:7:-C2o6nstraints::Simple::Library::Base(3)