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 Internal code now calls C<< ->meta >> in fewer places. We'd like to
22 eventually stop calling C<< ->meta >> entirely so that users may rename
23 or exclude that method altogether. This work is not yet complete, but
24 the bulk of it, all the easy stuff, has been done. This release uses
25 C<Class::MOP::class_of> instead of C<< ->meta >>.
27 Added a C<duck_type> sugar function to L<Moose::Util::TypeConstraints>
28 to make integration with non-Moose classes easier. It simply checks if
29 C<< $obj->can() >> a list of methods.
33 Calling C<subtype> with a name as the only argument now throws an
34 exception. If you want an anonymous subtype do:
36 my $subtype = subtype as 'Foo';
38 This is related to the changes in version 0.71_01.
40 The C<is_needed> method in L<Moose::Meta::Method::Destructor> is now
41 only usable as a class method. Previously, it worked as a class or
42 object method, with a different internal implementation for each
45 The internals of making a class immutable changed a lot in Class::MOP
46 0.78_02, and Moose's internals have changed along with it. The
47 external C<< $metaclass->make_immutable >> method still works the same
52 A mutable class accepted C<< Foo->new(undef) >> without complaint,
53 while an immutable class would blow up with an unhelpful error. Now,
54 in both cases we throw a helpful error instead.
56 This "feature" was originally added to allow for cases such as this:
64 return My::Class->new($args);
66 But we decided this is a bad idea and a little too magical, because it
67 can easily mask real errors.
69 =head1 Version 0.71_01
71 Calling C<type> or C<subtype> without the sugar helpers (C<as>,
72 C<where>, C<message>) is now deprecated.
74 As a side effect, this meant we ended up using Perl prototypes on
75 C<as>, and code like this will no longer work:
77 use Moose::Util::TypeConstraints;
78 use Declare::Constraints::Simple -All;
84 Instead it must be changed to this:
89 where => IsArrayRef(IsInt)
93 If you want to maintain backwards compat with older versions of Moose,
94 you must explicitly test Moose's C<VERSION>:
96 if ( Moose->VERSION < 0.71_01 ) {
105 where => IsArrayRef(IsInt)
112 We no longer pass the meta-attribute object as a final argument to
113 triggers. This actually changed for inlined code a while back, but the
114 non-inlined version and the docs were still out of date.
116 If by some chance you actually used this feature, the workaround is
117 simple. You fetch the attribute object from out of the C<$self>
118 that is passed as the first argument to trigger, like so:
124 my ( $self, $value ) = @_;
125 my $attr = $self->meta->find_attribute_by_name('foo');
133 If you created a subtype and passed a parent that Moose didn't know
134 about, it simply ignored the parent. Now it automatically creates the
135 parent as a class type. This may not be what you want, but is less
138 You could declare a name with subtype such as "Foo!Bar". Moose would
139 accept this allowed, but if you used it in a parameterized type such
140 as "ArrayRef[Foo!Bar]" it wouldn't work. We now do some vetting on
141 names created via the sugar functions, so that they can only contain
142 alphanumerics, ":", and ".".
146 Methods created via an attribute can now fulfill a C<requires>
147 declaration for a role. Honestly we don't know why Stevan didn't make
148 this work originally, he was just insane or something.
150 Stack traces from inlined code will now report the line and file as
151 being in your class, as opposed to in Moose guts.
153 =head1 Version 0.62_02
155 When a class does not provide all of a role's required methods, the
156 error thrown now mentions all of the missing methods, as opposed to
157 just the first missing method.
159 Moose will no longer inline a constructor for your class unless it
160 inherits its constructor is inherited from Moose::Object, and will
161 warn when it doesn't inline. If you want to force inlining anyway,
162 pass C<< "replace_constructor => 1 >> to C<make_immutable>.
164 If you want to get rid of the warning, pass C<< inline_constructor =>
169 Removed the (deprecated) C<make_immutable> keyword.
171 Removing an attribute from a class now also removes delegation
172 (C<handles>) methods installed for that attribute. This is correct
173 behavior, but if you were wrongly relying on it you might get bit.
177 Roles now add methods by calling C<add_method>, not
178 C<alias_method>. They make sure to always provide a method object,
179 which will be cloned internally. This means that it is now possible to
180 track the source of a method provided by a role, and even follow its
181 history through intermediate roles. This means that methods added by
182 a role now show up when looking at a class's method list/map.
184 Parameter and Union args are now sorted, this makes Int|Str the same
185 constraint as Str|Int. Also, incoming type constraint strings are
186 normalized to remove all whitespace differences. This is mostly for
187 internals and should not affect outside code.
189 L<Moose::Exporter> will no longer remove a subroutine that the
190 exporting package re-exports. Moose re-exports the Carp::confess
191 function, among others. The reasoning is that we cannot know whether
192 you have also explicitly imported those functions for your own use, so
193 we err on the safe side and always keep them.
197 C<Moose::init_meta> should now be called as a method.
199 New modules for extension writers, L<Moose::Exporter> and
200 L<Moose::Util::MetaRole>.
202 =head1 Version 0.55_01
204 Implemented metaclass traits (and wrote a recipe for it):
206 use Moose -traits => 'Foo'
208 This should make writing small Moose extensions a little
213 Fixed C<coerce> to accept anon types just like C<subtype> can.
216 coerce $some_anon_type => from 'Str' => via { ... };
220 Added C<BUILDARGS>, a new step in C<< Moose::Object->new() >>.
224 Fixed how the C<< is => (ro|rw) >> works with custom defined
225 C<reader>, C<writer> and C<accessor> options. See the below table for
228 is => ro, writer => _foo # turns into (reader => foo, writer => _foo)
229 is => rw, writer => _foo # turns into (reader => foo, writer => _foo)
230 is => rw, accessor => _foo # turns into (accessor => _foo)
231 is => ro, accessor => _foo # error, accesor is rw
235 The C<before/around/after> method modifiers now support regexp
236 matching of method names. NOTE: this only works for classes, it is
237 currently not supported in roles, but, ... patches welcome.
239 The C<has> keyword for roles now accepts the same array ref form that
240 L<Moose>.pm does for classes.
242 A trigger on a read-only attribute is no longer an error, as it's
243 useful to trigger off of the constructor.
245 Subtypes of parameterizable types now are parameterizable types
250 Fixed issue where C<DEMOLISHALL> was eating the value in C<$@>, and so
251 not working correctly. It still kind of eats them, but so does vanilla
256 Inherited attributes may now be extended without restriction on the
257 type ('isa', 'does').
259 The entire set of Moose::Meta::TypeConstraint::* classes were
260 refactored in this release. If you were relying on their internals you
261 should test your code carefully.
265 Documenting the use of '+name' with attributes that come from recently
266 composed roles. It makes sense, people are using it, and so why not
267 just officially support it.
269 The C<< Moose::Meta::Class->create >> method now supports roles.
271 It is now possible to make anonymous enum types by passing C<enum> an
272 array reference instead of the C<< enum $name => @values >>.
276 Added the C<make_immutable> keyword as a shortcut to calling
277 C<make_immutable> on the meta object. This eventually got removed!
279 Made C<< init_arg => undef >> work in Moose. This means "do not accept
280 a constructor parameter for this attribute".
282 Type errors now use the provided message. Prior to this release they
287 Moose is now a postmodern object system :)
289 The Role system was completely refactored. It is 100% backwards
290 compat, but the internals were totally changed. If you relied on the
291 internals then you are advised to test carefully.
293 Added method exclusion and aliasing for Roles in this release.
295 Added the L<Moose::Util::TypeConstraints::OptimizedConstraints>
298 Passing a list of values to an accessor (which is only expecting one
299 value) used to be silently ignored, now it throws an error.
303 Added parameterized types and did a pretty heavy refactoring of the
304 type constraint system.
306 Better framework extendability and better support for "making your own
309 =head1 Version 0.25 or before
311 Honestly, you shouldn't be using versions of Moose that are this old,
312 so many bug fixes and speed improvements have been made you would be
313 crazy to not upgrade.
315 Also, I am tired of going through the Changelog so I am stopping here,
316 if anyone would like to continue this please feel free.
320 Stevan Little E<lt>stevan@iinteractive.comE<gt>
322 =head1 COPYRIGHT AND LICENSE
324 Copyright 2009 by Infinity Interactive, Inc.
326 L<http://www.iinteractive.com>
328 This library is free software; you can redistribute it and/or modify
329 it under the same terms as Perl itself.