5 Moose::Manual::Delta - Important Changes in Moose
9 This documents any important or noteworthy changes in Moose, with a
10 focus on backwards. This does duplicate data from the F<Changes> file,
11 but aims to provide more details and when possible workarounds.
13 Besides helping keep up with changes, you can also use this document
14 for finding the lowest version of Moose that supported a given
15 feature. If you encounter a problem and have a solution but don't see
16 it documented here, or think we missed an important feature, please
21 Added a C<duck_type> sugar function to L<Moose::Util::TypeConstraints>
22 to make integration with non-Moose classes easier. It simply checks if
23 C<< $obj->can() >> a list of methods.
27 Calling C<subtype> with a name as the only argument now throws an
28 exception. If you want an anonymous subtype do:
30 my $subtype = subtype as 'Foo';
32 This is related to the changes in version 0.71_01.
34 The C<is_needed> method in L<Moose::Meta::Method::Destructor> is now
35 only usable as a class method. Previously, it worked as a class or
36 object method, with a different internal implementation for each
39 The internals of making a class immutable changed a lot in Class::MOP
40 0.78_02, and Moose's internals have changed along with it. The
41 external C<< $metaclass->make_immutable >> method still works the same
46 A mutable class accepted C<< Foo->new(undef) >> without complaint,
47 while an immutable class would blow up with an unhelpful error. Now,
48 in both cases we throw a helpful error instead.
50 This "feature" was originally added to allow for cases such as this:
58 return My::Class->new($args);
60 But we decided this is a bad idea and a little too magical, because it
61 can easily mask real errors.
63 =head1 Version 0.71_01
65 Calling C<type> or C<subtype> without the sugar helpers (C<as>,
66 C<where>, C<message>) is now deprecated.
68 As a side effect, this meant we ended up using Perl prototypes on
69 C<as>, and code like this will no longer work:
71 use Moose::Util::TypeConstraints;
72 use Declare::Constraints::Simple -All;
78 Instead it must be changed to this:
83 where => IsArrayRef(IsInt)
87 If you want to maintain backwards compat with older versions of Moose,
88 you must explicitly test Moose's C<VERSION>:
90 if ( Moose->VERSION < 0.71_01 ) {
99 where => IsArrayRef(IsInt)
106 We no longer pass the meta-attribute object as a final argument to
107 triggers. This actually changed for inlined code a while back, but the
108 non-inlined version and the docs were still out of date.
110 If by some chance you actually used this feature, the workaround is
111 simple. You fetch the attribute object from out of the C<$self>
112 that is passed as the first argument to trigger, like so:
118 my ( $self, $value ) = @_;
119 my $attr = $self->meta->find_attribute_by_name('foo');
127 If you created a subtype and passed a parent that Moose didn't know
128 about, it simply ignored the parent. Now it automatically creates the
129 parent as a class type. This may not be what you want, but is less
132 You could declare a name with subtype such as "Foo!Bar". Moose would
133 accept this allowed, but if you used it in a parameterized type such
134 as "ArrayRef[Foo!Bar]" it wouldn't work. We now do some vetting on
135 names created via the sugar functions, so that they can only contain
136 alphanumerics, ":", and ".".
140 Methods created via an attribute can now fulfill a C<requires>
141 declaration for a role. Honestly we don't know why Stevan didn't make
142 this work originally, he was just insane or something.
144 Stack traces from inlined code will now report the line and file as
145 being in your class, as opposed to in Moose guts.
147 =head1 Version 0.62_02
149 When a class does not provide all of a role's required methods, the
150 error thrown now mentions all of the missing methods, as opposed to
151 just the first missing method.
153 Moose will no longer inline a constructor for your class unless it
154 inherits its constructor is inherited from Moose::Object, and will
155 warn when it doesn't inline. If you want to force inlining anyway,
156 pass C<< "replace_constructor => 1 >> to C<make_immutable>.
158 If you want to get rid of the warning, pass C<< inline_constructor =>
163 Removed the (deprecated) C<make_immutable> keyword.
165 Removing an attribute from a class now also removes delegation
166 (C<handles>) methods installed for that attribute. This is correct
167 behavior, but if you were wrongly relying on it you might get bit.
171 Roles now add methods by calling C<add_method>, not
172 C<alias_method>. They make sure to always provide a method object,
173 which will be cloned internally. This means that it is now possible to
174 track the source of a method provided by a role, and even follow its
175 history through intermediate roles. This means that methods added by
176 a role now show up when looking at a class's method list/map.
178 Parameter and Union args are now sorted, this makes Int|Str the same
179 constraint as Str|Int. Also, incoming type constraint strings are
180 normalized to remove all whitespace differences. This is mostly for
181 internals and should not affect outside code.
183 L<Moose::Exporter> will no longer remove a subroutine that the
184 exporting package re-exports. Moose re-exports the Carp::confess
185 function, among others. The reasoning is that we cannot know whether
186 you have also explicitly imported those functions for your own use, so
187 we err on the safe side and always keep them.
191 C<Moose::init_meta> should now be called as a method.
193 New modules for extension writers, L<Moose::Exporter> and
194 L<Moose::Util::MetaRole>.
196 =head1 Version 0.55_01
198 Implemented metaclass traits (and wrote a recipe for it):
200 use Moose -traits => 'Foo'
202 This should make writing small Moose extensions a little
207 Fixed C<coerce> to accept anon types just like C<subtype> can.
210 coerce $some_anon_type => from 'Str' => via { ... };
214 Added C<BUILDARGS>, a new step in C<< Moose::Object->new() >>.
218 Fixed how the C<< is => (ro|rw) >> works with custom defined
219 C<reader>, C<writer> and C<accessor> options. See the below table for
222 is => ro, writer => _foo # turns into (reader => foo, writer => _foo)
223 is => rw, writer => _foo # turns into (reader => foo, writer => _foo)
224 is => rw, accessor => _foo # turns into (accessor => _foo)
225 is => ro, accessor => _foo # error, accesor is rw
229 The C<before/around/after> method modifiers now support regexp
230 matching of method names. NOTE: this only works for classes, it is
231 currently not supported in roles, but, ... patches welcome.
233 The C<has> keyword for roles now accepts the same array ref form that
234 L<Moose>.pm does for classes.
236 A trigger on a read-only attribute is no longer an error, as it's
237 useful to trigger off of the constructor.
239 Subtypes of parameterizable types now are parameterizable types
244 Fixed issue where C<DEMOLISHALL> was eating the value in C<$@>, and so
245 not working correctly. It still kind of eats them, but so does vanilla
250 Inherited attributes may now be extended without restriction on the
251 type ('isa', 'does').
253 The entire set of Moose::Meta::TypeConstraint::* classes were
254 refactored in this release. If you were relying on their internals you
255 should test your code carefully.
259 Documenting the use of '+name' with attributes that come from recently
260 composed roles. It makes sense, people are using it, and so why not
261 just officially support it.
263 The C<< Moose::Meta::Class->create >> method now supports roles.
265 It is now possible to make anonymous enum types by passing C<enum> an
266 array reference instead of the C<< enum $name => @values >>.
270 Added the C<make_immutable> keyword as a shortcut to calling
271 C<make_immutable> on the meta object. This eventually got removed!
273 Made C<< init_arg => undef >> work in Moose. This means "do not accept
274 a constructor parameter for this attribute".
276 Type errors now use the provided message. Prior to this release they
281 Moose is now a postmodern object system :)
283 The Role system was completely refactored. It is 100% backwards
284 compat, but the internals were totally changed. If you relied on the
285 internals then you are advised to test carefully.
287 Added method exclusion and aliasing for Roles in this release.
289 Added the L<Moose::Util::TypeConstraints::OptimizedConstraints>
292 Passing a list of values to an accessor (which is only expecting one
293 value) used to be silently ignored, now it throws an error.
297 Added parameterized types and did a pretty heavy refactoring of the
298 type constraint system.
300 Better framework extendability and better support for "making your own
303 =head1 Version 0.25 or before
305 Honestly, you shouldn't be using versions of Moose that are this old,
306 so many bug fixes and speed improvements have been made you would be
307 crazy to not upgrade.
309 Also, I am tired of going through the Changelog so I am stopping here,
310 if anyone would like to continue this please feel free.
314 Stevan Little E<lt>stevan@iinteractive.comE<gt>
316 =head1 COPYRIGHT AND LICENSE
318 Copyright 2009 by Infinity Interactive, Inc.
320 L<http://www.iinteractive.com>
322 This library is free software; you can redistribute it and/or modify
323 it under the same terms as Perl itself.