1Class::Mix(3) User Contributed Perl Documentation Class::Mix(3)
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6 Class::Mix - dynamic class mixing
7
9 use Class::Mix qw(mix_class);
10 $foobar_object = mix_class("Foo", "Bar")->new;
12 use Class::Mix qw(genpkg);
14 $package = genpkg;
16 $package = genpkg("Digest::Foo::");
17
19 The "mix_class" function provided by this module dynamically generates
20 `anonymous' classes with specified inheritance.
21
23 mix_class(CLASSES ...)
24 This function is used to dynamically generate `anonymous' classes
25 by mixing pre-existing classes. This is useful where an incomplete
26 class requires use of a mixin in order to become instantiable,
27 several suitable mixins are available, and it is desired to make
28 the choice between mixins at runtime.
29 The function takes as its argument list the desired @ISA list of
31 the mixture class to be created; that is, a list of names of
32 classes to inherit from. It generates a class with the specified
33 inheritance, and returns its name. The same class will be returned
34 by repeated invocations with the same class list. The returned
35 name may be used to call a constructor or other class methods of
36 the mixed class.
37 A class name must be returned because there is no such thing as an
39 anonymous class in Perl. Classes are referenced by name. The
40 names that are generated by this function are unique and
41 insignificant. See "genpkg" below for more information.
42 If fewer than two classes to inherit from are specified, the
44 function does not bother to generate a new class. If only one
45 class is specified then that class is returned. If no classes are
46 specified then "UNIVERSAL" is returned. This provides the desired
47 inheritance without creating superfluous classes.
48 This function relies on the classes it returns remaining unmodified
50 in order to be returned by future invocations. If you want to
51 modify your dynamically-generated `anonymous' classes, use "genpkg"
52 (below).
53 genpkg([PREFIX])
55 This function selects and returns a package name that has not been
56 previously used. The name returned is an ordinary bareword-form
57 package name, and can be used as the second argument to "bless" and
58 in all other ways that package names are used. The package is
59 initially empty.
60 The package names returned by this function are of a type that
62 should not be used as ordinary fixed module names. However, it is
63 not possible to entirely prevent a clash. This function checks
64 that the package name it is about to return has not already been
65 used, and will avoid returning such names, but it cannot guarantee
66 that a later-loaded module will not create a clash.
67 PREFIX, if present, specifies where the resulting package will go.
69 It must be either the empty string (to create a top-level package)
70 or a bareword followed by "::" (to create a package under that
71 name). For example, "Digest::" could be specified to ensure that
72 the resulting package has a name starting with "Digest::", so that
73 "Digest->new" will accept it as the name of a message digest
74 algorithm.
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77 Class::Generate
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80 Andrew Main (Zefram) <zefram@fysh.org>
81
83 Copyright (C) 2004, 2006, 2009 Andrew Main (Zefram) <zefram@fysh.org>
84
86 This module is free software; you can redistribute it and/or modify it
87 under the same terms as Perl itself.
88perl v5.12.0 2010-04-30 Class::Mix(3)