Provided by: libmoose-perl_2.2206-1_amd64 bug

NAME

       Moose::Manual::Delta - Important Changes in Moose

VERSION

       version 2.2206

DESCRIPTION

       This documents any important or noteworthy changes in Moose, with a focus on things that
       affect backwards compatibility. This does duplicate data from the Changes file, but aims
       to provide more details and when possible workarounds.

       Besides helping keep up with changes, you can also use this document for finding the
       lowest version of Moose that supported a given feature.  If you encounter a problem and
       have a solution but don't see it documented here, or think we missed an important feature,
       please send us a patch.

2.1400

       Overloading implementation has changed
           Overloading meta information used to be implemented by a
           "Class::MOP::Method::Overload" class. This class has been removed, and overloading is
           now implemented by Class::MOP::Overload. Overloading is not really equivalent to a
           method, so the former implementation didn't work properly for various cases.

           All of the overloading-related methods for classes and roles have the same names, but
           those methods now return Class::MOP::Overload objects.

       Core support for overloading in roles
           Roles which use overloading now pass that overloading onto other classes (and roles)
           which consume that role.

           This works much like MooseX::Role::WithOverloading, except that we properly detect
           overloading conflicts during role summation and when applying one role to another.
           MooseX::Role::WithOverloading did not do any conflict detection.

           If you want to write code that uses overloading and works with previous versions of
           Moose and this one, upgrade to MooseX::Role::WithOverloading version 0.15 or greater.
           That version will detect when Moose itself handles overloading and get out of the way.

2.1200

       Classes created by Moose are now registered in %INC
           This means that this will no longer die (and will also no longer try to load
           "Foo.pm"):

             {
                 package Foo;
                 use Moose;
             }

             # ...

             use Foo;

           If you're using the MOP, this behavior will occur when the "create" (or
           "create_anon_class") method is used, but not when the "initialize" method is used.

       Moose now uses Module::Runtime instead of Class::Load to load classes
           Class::Load has always had some weird issues with the ways that it tries to figure out
           if a class is loaded. For instance, extending an empty package was previously
           impossible, because Class::Load would think that the class failed to load, even though
           that is a perfectly valid thing to do. It was also difficult to deal with modules like
           IO::Handle, which partially populate several other packages when they are loaded (so
           calling "load_class" on 'IO::Handle' followed by 'IO::File' could end up with a broken
           "IO::File", in some cases).

           Now, Moose uses the same mechanisms as perl itself to figure out if a class is loaded.
           A class is considered to be loaded if its entry in %INC is set. Perl sets the %INC
           entry for you automatically whenever a file is loaded via "use" or "require". Also, as
           mentioned above, Moose also now sets the %INC entry for any classes defined with it,
           even if they aren't loaded from a separate file. This does however mean that if you
           are trying to use Moose with non-Moose classes defined in the same file, then you will
           need to set %INC manually now, where it may have worked in the past. For instance:

             {
                 package My::NonMoose;

                 sub new { bless {}, shift }

                 $INC{'My/NonMoose.pm'} = __FILE__;
                 # alternatively:
                 # use Module::Runtime 'module_notional_filename';
                 # $INC{module_notional_filename(__PACKAGE__)} = __FILE__;
             }

             {
                 package My::Moose;
                 use Moose;

                 extends 'My::NonMoose';
             }

           If you don't do this, you will get an error message about not being able to locate
           "My::NonMoose" in @INC. We hope that this case will be fairly rare.

       The Class::Load wrapper functions in Class::MOP have been deprecated
           "Class::MOP::load_class", "Class::MOP::is_class_loaded", and
           "Class::MOP::load_first_existing_class" have been deprecated. They have been
           undocumented and discouraged since version 2.0200. You should replace their use with
           the corresponding functions in Class::Load, or just use Module::Runtime directly.

       The non-arrayref forms of "enum" and "duck_type" have been deprecated
           Originally, "enum" could be called like this:

             enum('MyType' => qw(foo bar baz))

           This was confusing, however (since it was different from the syntax for anonymous enum
           types), and it makes error checking more difficult (since you can't tell just by
           looking whether "enum('Foo', 'Bar', 'Baz')" was intended to be a type named "Foo" with
           elements of "Bar" and "Baz", or if this was actually a mistake where someone got the
           syntax for an anonymous enum type wrong). This all also applies to "duck_type".

           Calling "enum" and "duck_type" with a list of arguments as described above has been
           undocumented since version 0.93, and is now deprecated. You should replace

             enum MyType => qw(foo bar baz);

           in your code with

             enum MyType => [qw(foo bar baz)];

       Moose string exceptions have been replaced by Moose exception objects
           Previously, Moose threw string exceptions on error conditions, which were not so
           verbose. All those string exceptions have now been converted to exception objects,
           which provide very detailed information about the exceptions. These exception objects
           provide a string overload that matches the previous exception message, so in most
           cases you should not have to change your code.

           For learning about the usage of Moose exception objects, read
           Moose::Manual::Exceptions. Individual exceptions are documented in
           Moose::Manual::Exceptions::Manifest.

           This work was funded as part of the GNOME Outreach Program for Women.

2.1000

       The Num type is now stricter
           The "Num" type used to accept anything that fits Perl's notion of a number, which
           included Inf, NaN, and strings like " 1234 \n".  We believe that the type constraint
           should indicate "this is a number", not "this coerces to a number".  Therefore, Num
           now only accepts integers, floating point numbers (both in decimal notation and
           exponential notation), 0, .0, 0.0, etc.

           If you want the old behavior you can use the "LaxNum" type in MooseX::Types::LaxNum.

       You can use Specio instead of core Moose types
           The Specio distribution is an experimental new type system intended to eventually
           replace the core Moose types, but yet also work with things like Moo and Mouse and
           anything else. Right now this is all speculative, but at least you can use Specio with
           Moose.

2.0600

       "->init_meta" is even less reliable at loading extensions
           Previously, calling "MooseX::Foo->init_meta(@_)" (and nothing else) from within your
           own "init_meta" had a decent chance of doing something useful.  This was never
           supported behavior, and didn't always work anyway. Due to some implementation
           adjustments, this now has a smaller chance of doing something useful, which could
           break code that was expecting it to continue doing useful things. Code that does this
           should instead just call "MooseX::Foo->import({ into => $into })".

       All the Cookbook recipes have been renamed
           We've given them all descriptive names, rather than numbers. This makes it easier to
           talk about them, and eliminates the need to renumber recipes in order to reorder them
           or delete one.

2.0400

       The parent of a union type is its components' nearest common ancestor
           Previously, union types considered all of their component types their parent types.
           This was incorrect because parent types are defined as types that must be satisfied in
           order for the child type to be satisfied, but in a union, validating as any parent
           type will validate against the entire union. This has been changed to find the nearest
           common ancestor for all of its components. For example, a union of "Int|ArrayRef[Int]"
           now has a parent of "Defined".

       Union types consider all members in the "is_subtype_of" and "is_a_type_of" methods
           Previously, a union type would report itself as being of a subtype of a type if any of
           its member types were subtypes of that type. This was incorrect because any value that
           passes a subtype constraint must also pass a parent constraint. This has changed so
           that all of its member types must be a subtype of the specified type.

       Enum types now work with just one value
           Previously, an "enum" type needed to have two or more values.  Nobody knew why, so we
           fixed it.

       Methods defined in UNIVERSAL now appear in the MOP
           Any method introspection methods that look at methods from parent classes now find
           methods defined in UNIVERSAL. This includes methods like "$class->get_all_methods" and
           "$class->find_method_by_name".

           This also means that you can now apply method modifiers to these methods.

       Hand-optimized type constraint code causes a deprecation warning
           If you provide an optimized sub ref for a type constraint, this now causes a
           deprecation warning. Typically, this comes from passing an "optimize_as" parameter to
           "subtype", but it could also happen if you create a Moose::Meta::TypeConstraint object
           directly.

           Use the inlining feature ("inline_as") added in 2.0100 instead.

       "Class::Load::load_class" and "is_class_loaded" have been removed
           The "Class::MOP::load_class" and "Class::MOP::is_class_loaded" subroutines are no
           longer documented, and will cause a deprecation warning in the future. Moose now uses
           Class::Load to provide this functionality, and you should do so as well.

2.0205

       Array and Hash native traits provide a "shallow_clone" method
           The Array and Hash native traits now provide a "shallow_clone" method, which will
           return a reference to a new container with the same contents as the attribute's
           reference.

2.0200

       Hand-optimized type constraint code is deprecated in favor of inlining
           Moose allows you to provide a hand-optimized version of a type constraint's subroutine
           reference. This version allows type constraints to generate inline code, and you
           should use this inlining instead of providing a hand-optimized subroutine reference.

           This affects the "optimize_as" sub exported by Moose::Util::TypeConstraints. Use
           "inline_as" instead.

           This will start warning in the 2.0300 release.

2.0002

       More useful type constraint error messages
           If you have Devel::PartialDump version 0.14 or higher installed, Moose's type
           constraint error messages will use it to display the invalid value, rather than just
           displaying it directly. This will generally be much more useful. For instance, instead
           of this:

             Attribute (foo) does not pass the type constraint because: Validation failed for 'ArrayRef[Int]' with value ARRAY(0x275eed8)

           the error message will instead look like

             Attribute (foo) does not pass the type constraint because: Validation failed for 'ArrayRef[Int]' with value [ "a" ]

           Note that Devel::PartialDump can't be made a direct dependency at the moment, because
           it uses Moose itself, but we're considering options to make this easier.

2.0000

       Roles have their own default attribute metaclass
           Previously, when a role was applied to a class, it would use the attribute metaclass
           defined in the class when copying over the attributes in the role.  This was wrong,
           because for instance, using MooseX::FollowPBP in the class would end up renaming all
           of the accessors generated by the role, some of which may be being called in the role,
           causing it to break. Roles now keep track of their own attribute metaclass to use by
           default when being applied to a class (defaulting to Moose::Meta::Attribute). This is
           modifiable using Moose::Util::MetaRole by passing the "applied_attribute" key to the
           "role_metaroles" option, as in:

               Moose::Util::MetaRole::apply_metaroles(
                   for => __PACKAGE__,
                   class_metaroles => {
                       attribute => ['My::Meta::Role::Attribute'],
                   },
                   role_metaroles => {
                       applied_attribute => ['My::Meta::Role::Attribute'],
                   },
               );

       Class::MOP has been folded into the Moose dist
           Moose and Class::MOP are tightly related enough that they have always had to be kept
           pretty closely in step in terms of versions. Making them into a single dist should
           simplify the upgrade process for users, as it should no longer be possible to upgrade
           one without the other and potentially cause issues. No functionality has changed, and
           this should be entirely transparent.

       Moose's conflict checking is more robust and useful
           There are two parts to this. The most useful one right now is that Moose will ship
           with a "moose-outdated" script, which can be run at any point to list the modules
           which are installed that conflict with the installed version of Moose.  After
           upgrading Moose, running "moose-outdated | cpanm" should be sufficient to ensure that
           all of the Moose extensions you use will continue to work.

           The other part is that Moose's "META.json" file will also specify the conflicts under
           the "x_conflicts" (now "x_breaks") key. We are working with the Perl tool chain
           developers to try to get conflicts support added to CPAN clients, and if/when that
           happens, the metadata already exists, and so the conflict checking will become
           automatic.

       The lazy_build attribute feature is discouraged
           While not deprecated, we strongly discourage you from using this feature.

       Most deprecated APIs/features are slated for removal in Moose 2.0200
           Most of the deprecated APIs and features in Moose will start throwing an error in
           Moose 2.0200. Some of the features will go away entirely, and some will simply throw
           an error.

           The things on the chopping block are:

           •       Old public methods in Class::MOP and Moose

                   This includes things like "Class::MOP::Class->get_attribute_map",
                   "Class::MOP::Class->construct_instance", and many others. These were
                   deprecated in Class::MOP 0.80_01, released on April 5, 2009.

                   These methods will be removed entirely in Moose 2.0200.

           •       Old public functions in Class::MOP

                   This include "Class::MOP::subname", "Class::MOP::in_global_destruction", and
                   the "Class::MOP::HAS_ISAREV" constant. The first two were deprecated in 0.84,
                   and the last in 0.80. Class::MOP 0.84 was released on May 12, 2009.

                   These functions will be removed entirely in Moose 2.0200.

           •       The "alias" and "excludes" option for role composition

                   These were renamed to "-alias" and "-excludes" in Moose 0.89, released on
                   August 13, 2009.

                   Passing these will throw an error in Moose 2.0200.

           •       The old Moose::Util::MetaRole API

                   This include the "apply_metaclass_roles()" function, as well as passing the
                   "for_class" or any key ending in "_roles" to "apply_metaroles()". This was
                   deprecated in Moose 0.93_01, released on January 4, 2010.

                   These will all throw an error in Moose 2.0200.

           •       Passing plain lists to "type()" or "subtype()"

                   The old API for these functions allowed you to pass a plain list of parameter,
                   rather than a list of hash references (which is what "as()", "where", etc.
                   return). This was deprecated in Moose 0.71_01, released on February 22, 2009.

                   This will throw an error in Moose 2.0200.

           •       The Role subtype

                   This subtype was deprecated in Moose 0.84, released on June 26, 2009.

                   This will be removed entirely in Moose 2.0200.

1.21

       •   New release policy

           As of the 2.0 release, Moose now has an official release and support policy,
           documented in Moose::Manual::Support. All API changes will now go through a
           deprecation cycle of at least one year, after which the deprecated API can be removed.
           Deprecations and removals will only happen in major releases.

           In between major releases, we will still make minor releases to add new features, fix
           bugs, update documentation, etc.

1.16

       Configurable stacktraces
           Classes which use the Moose::Error::Default error class can now have stacktraces
           disabled by setting the "MOOSE_ERROR_STYLE" env var to "croak".  This is experimental,
           fairly incomplete, and won't work in all cases (because Moose's error system in
           general is all of these things), but this should allow for reducing at least some of
           the verbosity in most cases.

1.15

       Native Delegations
           In previous versions of Moose, the Native delegations were created as closures. The
           generated code was often quite slow compared to doing the same thing by hand. For
           example, the Array's push delegation ended up doing something like this:

             push @{ $self->$reader() }, @_;

           If the attribute was created without a reader, the $reader sub reference followed a
           very slow code path. Even with a reader, this is still slower than it needs to be.

           Native delegations are now generated as inline code, just like other accessors, so we
           can access the slot directly.

           In addition, native traits now do proper constraint checking in all cases. In
           particular, constraint checking has been improved for array and hash references.
           Previously, only the contained type (the "Str" in "HashRef[Str]") would be checked
           when a new value was added to the collection. However, if there was a constraint that
           applied to the whole value, this was never checked.

           In addition, coercions are now called on the whole value.

           The delegation methods now do more argument checking. All of the methods check that a
           valid number of arguments were passed to the method. In addition, the delegation
           methods check that the arguments are sane (array indexes, hash keys, numbers, etc.)
           when applicable. We have tried to emulate the behavior of Perl builtins as much as
           possible.

           Finally, triggers are called whenever the value of the attribute is changed by a
           Native delegation.

           These changes are only likely to break code in a few cases.

           The inlining code may or may not preserve the original reference when changes are
           made. In some cases, methods which change the value may replace it entirely. This will
           break tied values.

           If you have a typed arrayref or hashref attribute where the type enforces a constraint
           on the whole collection, this constraint will now be checked. It's possible that code
           which previously ran without errors will now cause the constraint to fail. However,
           presumably this is a good thing ;)

           If you are passing invalid arguments to a delegation which were previously being
           ignored, these calls will now fail.

           If your code relied on the trigger only being called for a regular writer, that may
           cause problems.

           As always, you are encouraged to test before deploying the latest version of Moose to
           production.

       Defaults is and default for String, Counter, and Bool
           A few native traits (String, Counter, Bool) provide default values of "is" and
           "default" when you created an attribute. Allowing them to provide these values is now
           deprecated. Supply the value yourself when creating the attribute.

       The "meta" method
           Moose and Class::MOP have been cleaned up internally enough to make the "meta" method
           that you get by default optional. "use Moose" and "use Moose::Role" now can take an
           additional "-meta_name" option, which tells Moose what name to use when installing the
           "meta" method. Passing "undef" to this option suppresses generation of the "meta"
           method entirely. This should be useful for users of modules which also use a "meta"
           method or function, such as Curses or Rose::DB::Object.

1.09

       All deprecated features now warn
           Previously, deprecation mostly consisted of simply saying "X is deprecated" in the
           Changes file. We were not very consistent about actually warning. Now, all deprecated
           features still present in Moose actually give a warning. The warning is issued once
           per calling package. See Moose::Deprecated for more details.

       You cannot pass "coerce => 1" unless the attribute's type constraint has a coercion
           Previously, this was accepted, and it sort of worked, except that if you attempted to
           set the attribute after the object was created, you would get a runtime error.

           Now you will get a warning when you attempt to define the attribute.

       "no Moose", "no Moose::Role", and "no Moose::Exporter" no longer unimport strict and
       warnings
           This change was made in 1.05, and has now been reverted. We don't know if the user has
           explicitly loaded strict or warnings on their own, and unimporting them is just broken
           in that case.

       Reversed logic when defining which options can be changed
           Moose::Meta::Attribute now allows all options to be changed in an overridden
           attribute. The previous behaviour required each option to be whitelisted using the
           "legal_options_for_inheritance" method. This method has been removed, and there is a
           new method, "illegal_options_for_inheritance", which can now be used to prevent
           certain options from being changeable.

           In addition, we only throw an error if the illegal option is actually changed. If the
           superclass didn't specify this option at all when defining the attribute, the subclass
           version can still add it as an option.

           Example of overriding this in an attribute trait:

             package Bar::Meta::Attribute;
             use Moose::Role;

             has 'my_illegal_option' => (
                 isa => 'CodeRef',
                 is  => 'rw',
             );

             around illegal_options_for_inheritance => sub {
                 return ( shift->(@_), qw/my_illegal_option/ );
             };

1.05

       "BUILD" in Moose::Object methods are now called when calling "new_object"
           Previously, "BUILD" methods would only be called from "Moose::Object::new", but now
           they are also called when constructing an object via "Moose::Meta::Class::new_object".
           "BUILD" methods are an inherent part of the object construction process, and this
           should make "$meta->new_object" actually usable without forcing people to use
           "$meta->name->new".

       "no Moose", "no Moose::Role", and "no Moose::Exporter" now unimport strict and warnings
           In the interest of having "no Moose" clean up everything that "use Moose" does in the
           calling scope, "no Moose" (as well as all other Moose::Exporter-using modules) now
           unimports strict and warnings.

       Metaclass compatibility checking and fixing should be much more robust
           The metaclass compatibility checking and fixing algorithms have been completely
           rewritten, in both Class::MOP and Moose. This should resolve many confusing errors
           when dealing with non-Moose inheritance and with custom metaclasses for things like
           attributes, constructors, etc. For correct code, the only thing that should require a
           change is that custom error metaclasses must now inherit from Moose::Error::Default.

1.02

       Moose::Meta::TypeConstraint::Class is_subtype_of behavior
           Earlier versions of is_subtype_of would incorrectly return true when called with
           itself, its own TC name or its class name as an argument. (i.e.
           $foo_tc->is_subtype_of('Foo') == 1) This behavior was a caused by "isa" being checked
           before the class name. The old behavior can be accessed with is_type_of

1.00

       Moose::Meta::Attribute::Native::Trait::Code no longer creates reader methods by default
           Earlier versions of Moose::Meta::Attribute::Native::Trait::Code created read-only
           accessors for the attributes it's been applied to, even if you didn't ask for it with
           "is => 'ro'". This incorrect behaviour has now been fixed.

0.95

       Moose::Util add_method_modifier behavior
           add_method_modifier (and subsequently the sugar functions Moose::before, Moose::after,
           and Moose::around) can now accept arrayrefs, with the same behavior as lists. Types
           other than arrayref and regexp result in an error.

0.93_01 and 0.94

       Moose::Util::MetaRole API has changed
           The "apply_metaclass_roles" function is now called "apply_metaroles". The way
           arguments are supplied has been changed to force you to distinguish between metaroles
           applied to Moose::Meta::Class (and helpers) versus Moose::Meta::Role.

           The old API still works, but will warn in a future release, and eventually be removed.

       Moose::Meta::Role has real attributes
           The attributes returned by Moose::Meta::Role are now instances of the
           Moose::Meta::Role::Attribute class, instead of bare hash references.

       "no Moose" now removes "blessed" and "confess"
           Moose is now smart enough to know exactly what it exported, even when it re-exports
           functions from other packages. When you unimport Moose, it will remove these functions
           from your namespace unless you also imported them directly from their respective
           packages.

           If you have a "no Moose" in your code before you call "blessed" or "confess", your
           code will break. You can either move the "no Moose" call later in your code, or
           explicitly import the relevant functions from the packages that provide them.

       Moose::Exporter is smarter about unimporting re-exports
           The change above comes from a general improvement to Moose::Exporter. It will now
           unimport any function it exports, even if that function is a re-export from another
           package.

       Attributes in roles can no longer override class attributes with "+foo"
           Previously, this worked more or less accidentally, because role attributes weren't
           objects. This was never documented, but a few MooseX modules took advantage of this.

       The composition_class_roles attribute in Moose::Meta::Role is now a method
           This was done to make it possible for roles to alter the list of composition class
           roles by applying a method modifiers. Previously, this was an attribute and MooseX
           modules override it. Since that no longer works, this was made a method.

           This should be an attribute, so this may switch back to being an attribute in the
           future if we can figure out how to make this work.

0.93

       Calling $object->new() is no longer deprecated
           We decided to undeprecate this. Now it just works.

       Both "get_method_map" and "get_attribute_map" is deprecated
           These metaclass methods were never meant to be public, and they are both now
           deprecated. The work around if you still need the functionality they provided is to
           iterate over the list of names manually.

               my %fields = map { $_ => $meta->get_attribute($_) } $meta->get_attribute_list;

           This was actually a change in Class::MOP, but this version of Moose requires a version
           of Class::MOP that includes said change.

0.90

       Added Native delegation for Code refs
           See Moose::Meta::Attribute::Native::Trait::Code for details.

       Calling $object->new() is deprecated
           Moose has long supported this, but it's never really been documented, and we don't
           think this is a good practice. If you want to construct an object from an existing
           object, you should provide some sort of alternate constructor like "$object->clone".

           Calling "$object->new" now issues a warning, and will be an error in a future release.

       Moose no longer warns if you call "make_immutable" for a class with mutable ancestors
           While in theory this is a good thing to warn about, we found so many exceptions to
           this that doing this properly became quite problematic.

0.89_02

       New Native delegation methods from List::Util and List::MoreUtils
           In particular, we now have "reduce", "shuffle", "uniq", and "natatime".

       The Moose::Exporter with_caller feature is now deprecated
           Use "with_meta" instead. The "with_caller" option will start warning in a future
           release.

       Moose now warns if you call "make_immutable" for a class with mutable ancestors
           This is dangerous because modifying a class after a subclass has been immutabilized
           will lead to incorrect results in the subclass, due to inlining, caching, etc. This
           occasionally happens accidentally, when a class loads one of its subclasses in the
           middle of its class definition, so pointing out that this may cause issues should be
           helpful. Metaclasses (classes that inherit from Class::MOP::Object) are currently
           exempt from this check, since at the moment we aren't very consistent about which
           metaclasses we immutabilize.

       "enum" and "duck_type" now take arrayrefs for all forms
           Previously, calling these functions with a list would take the first element of the
           list as the type constraint name, and use the remainder as the enum values or method
           names. This makes the interface inconsistent with the anon-type forms of these
           functions (which must take an arrayref), and a free-form list where the first value is
           sometimes special is hard to validate (and harder to give reasonable error messages
           for). These functions have been changed to take arrayrefs in all their forms - so,
           "enum 'My::Type' => [qw(foo bar)]" is now the preferred way to create an enum type
           constraint. The old syntax still works for now, but it will hopefully be deprecated
           and removed in a future release.

0.89_01

       Moose::Meta::Attribute::Native has been moved into the Moose core from
       MooseX::AttributeHelpers.  Major changes include:

       "traits", not "metaclass"
           Method providers are only available via traits.

       "handles", not "provides" or "curries"
           The "provides" syntax was like core Moose "handles => HASHREF" syntax, but with the
           keys and values reversed.  This was confusing, and AttributeHelpers now uses "handles
           => HASHREF" in a way that should be intuitive to anyone already familiar with how it
           is used for other attributes.

           The "curries" functionality provided by AttributeHelpers has been generalized to apply
           to all cases of "handles => HASHREF", though not every piece of functionality has been
           ported (currying with a CODEREF is not supported).

       "empty" is now "is_empty", and means empty, not non-empty
           Previously, the "empty" method provided by Arrays and Hashes returned true if the
           attribute was not empty (no elements).  Now it returns true if the attribute is empty.
           It was also renamed to "is_empty", to reflect this.

       "find" was renamed to "first", and "first" and "last" were removed
           List::Util refers to the functionality that we used to provide under "find" as first,
           so that will likely be more familiar (and will fit in better if we decide to add more
           List::Util functions). "first" and "last" were removed, since their functionality is
           easily duplicated with curries of "get".

       Helpers that take a coderef of one argument now use $_
           Subroutines passed as the first argument to "first", "map", and "grep" now receive
           their argument in $_ rather than as a parameter to the subroutine.  Helpers that take
           a coderef of two or more arguments remain using the argument list (there are technical
           limitations to using $a and $b like "sort" does).

           See Moose::Meta::Attribute::Native for the new documentation.

       The "alias" and "excludes" role parameters have been renamed to "-alias" and "-excludes".
       The old names still work, but new code should use the new names, and eventually the old
       ones will be deprecated and removed.

0.89

       "use Moose -metaclass => 'Foo'" now does alias resolution, just like "-traits" (and the
       "metaclass" and "traits" options to "has").

       Added two functions "meta_class_alias" and "meta_attribute_alias" to Moose::Util, to
       simplify aliasing metaclasses and metatraits. This is a wrapper around the old

         package Moose::Meta::Class::Custom::Trait::FooTrait;
         sub register_implementation { 'My::Meta::Trait' }

       way of doing this.

0.84

       When an attribute generates no accessors, we now warn. This is to help users who forget
       the "is" option. If you really do not want any accessors, you can use "is => 'bare'". You
       can maintain back compat with older versions of Moose by using something like:

           ($Moose::VERSION >= 0.84 ? is => 'bare' : ())

       When an accessor overwrites an existing method, we now warn. To work around this warning
       (if you really must have this behavior), you can explicitly remove the method before
       creating it as an accessor:

           sub foo {}

           __PACKAGE__->meta->remove_method('foo');

           has foo => (
               is => 'ro',
           );

       When an unknown option is passed to "has", we now warn. You can silence the warning by
       fixing your code. :)

       The "Role" type has been deprecated. On its own, it was useless, since it just checked
       "$object->can('does')". If you were using it as a parent type, just call
       "role_type('Role::Name')" to create an appropriate type instead.

0.78

       "use Moose::Exporter;" now imports "strict" and "warnings" into packages that use it.

0.77

       "DEMOLISHALL" and "DEMOLISH" now receive an argument indicating whether or not we are in
       global destruction.

0.76

       Type constraints no longer run coercions for a value that already matches the constraint.
       This may affect some (arguably buggy) edge case coercions that rely on side effects in the
       "via" clause.

0.75

       Moose::Exporter now accepts the "-metaclass" option for easily overriding the metaclass
       (without metaclass). This works for classes and roles.

0.74

       Added a "duck_type" sugar function to Moose::Util::TypeConstraints to make integration
       with non-Moose classes easier. It simply checks if "$obj->can()" a list of methods.

       A number of methods (mostly inherited from Class::MOP) have been renamed with a leading
       underscore to indicate their internal-ness. The old method names will still work for a
       while, but will warn that the method has been renamed. In a few cases, the method will be
       removed entirely in the future. This may affect MooseX authors who were using these
       methods.

0.73

       Calling "subtype" with a name as the only argument now throws an exception. If you want an
       anonymous subtype do:

           my $subtype = subtype as 'Foo';

       This is related to the changes in version 0.71_01.

       The "is_needed" method in Moose::Meta::Method::Destructor is now only usable as a class
       method. Previously, it worked as a class or object method, with a different internal
       implementation for each version.

       The internals of making a class immutable changed a lot in Class::MOP 0.78_02, and Moose's
       internals have changed along with it. The external "$metaclass->make_immutable" method
       still works the same way.

0.72

       A mutable class accepted "Foo->new(undef)" without complaint, while an immutable class
       would blow up with an unhelpful error. Now, in both cases we throw a helpful error
       instead.

       This "feature" was originally added to allow for cases such as this:

         my $args;

         if ( something() ) {
             $args = {...};
         }

         return My::Class->new($args);

       But we decided this is a bad idea and a little too magical, because it can easily mask
       real errors.

0.71_01

       Calling "type" or "subtype" without the sugar helpers ("as", "where", "message") is now
       deprecated.

       As a side effect, this meant we ended up using Perl prototypes on "as", and code like this
       will no longer work:

         use Moose::Util::TypeConstraints;
         use Declare::Constraints::Simple -All;

         subtype 'ArrayOfInts'
             => as 'ArrayRef'
             => IsArrayRef(IsInt);

       Instead it must be changed to this:

         subtype(
             'ArrayOfInts' => {
                 as    => 'ArrayRef',
                 where => IsArrayRef(IsInt)
             }
         );

       If you want to maintain backwards compat with older versions of Moose, you must explicitly
       test Moose's "VERSION":

         if ( Moose->VERSION < 0.71_01 ) {
             subtype 'ArrayOfInts'
                 => as 'ArrayRef'
                 => IsArrayRef(IsInt);
         }
         else {
             subtype(
                 'ArrayOfInts' => {
                     as    => 'ArrayRef',
                     where => IsArrayRef(IsInt)
                 }
             );
         }

0.70

       We no longer pass the meta-attribute object as a final argument to triggers. This actually
       changed for inlined code a while back, but the non-inlined version and the docs were still
       out of date.

       If by some chance you actually used this feature, the workaround is simple. You fetch the
       attribute object from out of the $self that is passed as the first argument to trigger,
       like so:

         has 'foo' => (
             is      => 'ro',
             isa     => 'Any',
             trigger => sub {
                 my ( $self, $value ) = @_;
                 my $attr = $self->meta->find_attribute_by_name('foo');

                 # ...
             }
         );

0.66

       If you created a subtype and passed a parent that Moose didn't know about, it simply
       ignored the parent. Now it automatically creates the parent as a class type. This may not
       be what you want, but is less broken than before.

       You could declare a name with subtype such as "Foo!Bar". Moose would accept this allowed,
       but if you used it in a parameterized type such as "ArrayRef[Foo!Bar]" it wouldn't work.
       We now do some vetting on names created via the sugar functions, so that they can only
       contain alphanumerics, ":", and ".".

0.65

       Methods created via an attribute can now fulfill a "requires" declaration for a role.
       Honestly we don't know why Stevan didn't make this work originally, he was just insane or
       something.

       Stack traces from inlined code will now report the line and file as being in your class,
       as opposed to in Moose guts.

0.62_02

       When a class does not provide all of a role's required methods, the error thrown now
       mentions all of the missing methods, as opposed to just the first missing method.

       Moose will no longer inline a constructor for your class unless it inherits its
       constructor from Moose::Object, and will warn when it doesn't inline. If you want to force
       inlining anyway, pass "replace_constructor => 1" to "make_immutable".

       If you want to get rid of the warning, pass "inline_constructor => 0".

0.62

       Removed the (deprecated) "make_immutable" keyword.

       Removing an attribute from a class now also removes delegation ("handles") methods
       installed for that attribute. This is correct behavior, but if you were wrongly relying on
       it you might get bit.

0.58

       Roles now add methods by calling "add_method", not "alias_method". They make sure to
       always provide a method object, which will be cloned internally. This means that it is now
       possible to track the source of a method provided by a role, and even follow its history
       through intermediate roles.  This means that methods added by a role now show up when
       looking at a class's method list/map.

       Parameter and Union args are now sorted, this makes Int|Str the same constraint as
       Str|Int. Also, incoming type constraint strings are normalized to remove all whitespace
       differences. This is mostly for internals and should not affect outside code.

       Moose::Exporter will no longer remove a subroutine that the exporting package re-exports.
       Moose re-exports the Carp::confess function, among others. The reasoning is that we cannot
       know whether you have also explicitly imported those functions for your own use, so we err
       on the safe side and always keep them.

0.56

       "Moose::init_meta" should now be called as a method.

       New modules for extension writers, Moose::Exporter and Moose::Util::MetaRole.

0.55_01

       Implemented metaclass traits (and wrote a recipe for it):

         use Moose -traits => 'Foo'

       This should make writing small Moose extensions a little easier.

0.55

       Fixed "coerce" to accept anon types just like "subtype" can.  So that you can do:

         coerce $some_anon_type => from 'Str' => via { ... };

0.51

       Added "BUILDARGS", a new step in "Moose::Object->new()".

0.49

       Fixed how the "is => (ro|rw)" works with custom defined "reader", "writer" and "accessor"
       options. See the below table for details:

         is => ro, writer => _foo    # turns into (reader => foo, writer => _foo)
         is => rw, writer => _foo    # turns into (reader => foo, writer => _foo)
         is => rw, accessor => _foo  # turns into (accessor => _foo)
         is => ro, accessor => _foo  # error, accesor is rw

0.45

       The "before/around/after" method modifiers now support regexp matching of method names.
       NOTE: this only works for classes, it is currently not supported in roles, but, ...
       patches welcome.

       The "has" keyword for roles now accepts the same array ref form that Moose.pm does for
       classes.

       A trigger on a read-only attribute is no longer an error, as it's useful to trigger off of
       the constructor.

       Subtypes of parameterizable types now are parameterizable types themselves.

0.44

       Fixed issue where "DEMOLISHALL" was eating the value in $@, and so not working correctly.
       It still kind of eats them, but so does vanilla perl.

0.41

       Inherited attributes may now be extended without restriction on the type ('isa', 'does').

       The entire set of Moose::Meta::TypeConstraint::* classes were refactored in this release.
       If you were relying on their internals you should test your code carefully.

0.40

       Documenting the use of '+name' with attributes that come from recently composed roles. It
       makes sense, people are using it, and so why not just officially support it.

       The "Moose::Meta::Class->create" method now supports roles.

       It is now possible to make anonymous enum types by passing "enum" an array reference
       instead of the "enum $name => @values".

0.37

       Added the "make_immutable" keyword as a shortcut to calling "make_immutable" on the meta
       object. This eventually got removed!

       Made "init_arg => undef" work in Moose. This means "do not accept a constructor parameter
       for this attribute".

       Type errors now use the provided message. Prior to this release they didn't.

0.34

       Moose is now a postmodern object system :)

       The Role system was completely refactored. It is 100% backwards compat, but the internals
       were totally changed. If you relied on the internals then you are advised to test
       carefully.

       Added method exclusion and aliasing for Roles in this release.

       Added the Moose::Util::TypeConstraints::OptimizedConstraints module.

       Passing a list of values to an accessor (which is only expecting one value) used to be
       silently ignored, now it throws an error.

0.26

       Added parameterized types and did a pretty heavy refactoring of the type constraint
       system.

       Better framework extensibility and better support for "making your own Moose".

0.25 or before

       Honestly, you shouldn't be using versions of Moose that are this old, so many bug fixes
       and speed improvements have been made you would be crazy to not upgrade.

       Also, I am tired of going through the Changelog so I am stopping here, if anyone would
       like to continue this please feel free.

AUTHORS

       •   Stevan Little <stevan@cpan.org>

       •   Dave Rolsky <autarch@urth.org>

       •   Jesse Luehrs <doy@cpan.org>

       •   Shawn M Moore <sartak@cpan.org>

       •   יובל קוג'מן (Yuval Kogman) <nothingmuch@woobling.org>

       •   Karen Etheridge <ether@cpan.org>

       •   Florian Ragwitz <rafl@debian.org>

       •   Hans Dieter Pearcey <hdp@cpan.org>

       •   Chris Prather <chris@prather.org>

       •   Matt S Trout <mstrout@cpan.org>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2006 by Infinity Interactive, Inc.

       This is free software; you can redistribute it and/or modify it under the same terms as
       the Perl 5 programming language system itself.