X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FMoo.pm;h=0dfaf8d1040b3ee00166ce6f9c2ec898bdf849c9;hb=c600e70640098ae6ad958dc7a07187464abd37d3;hp=545e80a3ead06dcce5437361a6794515a91bf5f7;hpb=f9755246a7eec67300ed639a439be560a12551db;p=gitmo%2FMoo.git diff --git a/lib/Moo.pm b/lib/Moo.pm index 545e80a..0dfaf8d 100644 --- a/lib/Moo.pm +++ b/lib/Moo.pm @@ -5,46 +5,67 @@ use Moo::_Utils; use B 'perlstring'; use Sub::Defer (); -our $VERSION = '0.091002'; # 0.91.2 +our $VERSION = '1.003001'; $VERSION = eval $VERSION; require Moo::sification; our %MAKERS; +sub _install_tracked { + my ($target, $name, $code) = @_; + $MAKERS{$target}{exports}{$name} = $code; + _install_coderef "${target}::${name}" => "Moo::${name}" => $code; +} + sub import { my $target = caller; my $class = shift; strictures->import; - return if $MAKERS{$target}; # already exported into this package - _install_coderef "${target}::extends" => "Moo::extends" => sub { - _load_module($_) for @_; - # Can't do *{...} = \@_ or 5.10.0's mro.pm stops seeing @ISA - @{*{_getglob("${target}::ISA")}{ARRAY}} = @_; - if (my $old = delete $Moo::MAKERS{$target}{constructor}) { - delete _getstash($target)->{new}; - Moo->_constructor_maker_for($target) - ->register_attribute_specs(%{$old->all_attribute_specs}); - } + if ($Role::Tiny::INFO{$target} and $Role::Tiny::INFO{$target}{is_role}) { + die "Cannot import Moo into a role"; + } + $MAKERS{$target} ||= {}; + _install_tracked $target => extends => sub { + $class->_set_superclasses($target, @_); + $class->_maybe_reset_handlemoose($target); + return; }; - _install_coderef "${target}::with" => "Moo::with" => sub { + _install_tracked $target => with => sub { require Moo::Role; - Moo::Role->apply_roles_to_package($target, $_[0]); + Moo::Role->apply_roles_to_package($target, @_); + $class->_maybe_reset_handlemoose($target); }; - $MAKERS{$target} = {}; - _install_coderef "${target}::has" => "Moo::has" => sub { - my ($name, %spec) = @_; - $class->_constructor_maker_for($target) - ->register_attribute_specs($name, \%spec); - $class->_accessor_maker_for($target) - ->generate_method($target, $name, \%spec); + _install_tracked $target => has => sub { + my $name_proto = shift; + my @name_proto = ref $name_proto eq 'ARRAY' ? @$name_proto : $name_proto; + if (@_ % 2 != 0) { + require Carp; + Carp::croak("Invalid options for " . join(', ', map "'$_'", @name_proto) + . " attribute(s): even number of arguments expected, got " . scalar @_) + } + my %spec = @_; + foreach my $name (@name_proto) { + # Note that when multiple attributes specified, each attribute + # needs a separate \%specs hashref + my $spec_ref = @name_proto > 1 ? +{%spec} : \%spec; + $class->_constructor_maker_for($target) + ->register_attribute_specs($name, $spec_ref); + $class->_accessor_maker_for($target) + ->generate_method($target, $name, $spec_ref); + $class->_maybe_reset_handlemoose($target); + } + return; }; foreach my $type (qw(before after around)) { - _install_coderef "${target}::${type}" => "Moo::${type}" => sub { + _install_tracked $target => $type => sub { require Class::Method::Modifiers; _install_modifier($target, $type, @_); + return; }; } + return if $MAKERS{$target}{is_class}; # already exported into this package + $MAKERS{$target}{is_class} = 1; { no strict 'refs'; @{"${target}::ISA"} = do { @@ -56,13 +77,51 @@ sub import { } } +sub unimport { + my $target = caller; + _unimport_coderefs($target, $MAKERS{$target}); +} + +sub _set_superclasses { + my $class = shift; + my $target = shift; + foreach my $superclass (@_) { + _load_module($superclass); + if ($INC{"Role/Tiny.pm"} && $Role::Tiny::INFO{$superclass}) { + require Carp; + Carp::croak("Can't extend role '$superclass'"); + } + } + # Can't do *{...} = \@_ or 5.10.0's mro.pm stops seeing @ISA + @{*{_getglob("${target}::ISA")}{ARRAY}} = @_; + if (my $old = delete $Moo::MAKERS{$target}{constructor}) { + delete _getstash($target)->{new}; + Moo->_constructor_maker_for($target) + ->register_attribute_specs(%{$old->all_attribute_specs}); + } + elsif (!$target->isa('Moo::Object')) { + Moo->_constructor_maker_for($target); + } + no warnings 'once'; # piss off. -- mst + $Moo::HandleMoose::MOUSE{$target} = [ + grep defined, map Mouse::Util::find_meta($_), @_ + ] if Mouse::Util->can('find_meta'); +} + +sub _maybe_reset_handlemoose { + my ($class, $target) = @_; + if ($INC{"Moo/HandleMoose.pm"}) { + Moo::HandleMoose::maybe_reinject_fake_metaclass_for($target); + } +} + sub _accessor_maker_for { my ($class, $target) = @_; return unless $MAKERS{$target}; $MAKERS{$target}{accessor} ||= do { my $maker_class = do { if (my $m = do { - if (my $defer_target = + if (my $defer_target = (Sub::Defer::defer_info($target->can('new'))||[])->[0] ) { my ($pkg) = ($defer_target =~ /^(.*)::[^:]+$/); @@ -107,7 +166,7 @@ sub _constructor_maker_for { } else { $moo_constructor = 1; # no other constructor, make a Moo one } - }; + } ($con ? ref($con) : 'Method::Generate::Constructor') ->new( package => $target, @@ -115,12 +174,14 @@ sub _constructor_maker_for { construction_string => ( $moo_constructor ? ($con ? $con->construction_string : undef) - : ('$class->'.$target.'::SUPER::new(@_)') + : ('$class->'.$target.'::SUPER::new($class->can(q[FOREIGNBUILDARGS]) ? $class->FOREIGNBUILDARGS(@_) : @_)') ), subconstructor_handler => ( ' if ($Moo::MAKERS{$class}) {'."\n" .' '.$class.'->_constructor_maker_for($class,'.perlstring($target).');'."\n" .' return $class->new(@_)'.";\n" + .' } elsif ($INC{"Moose.pm"} and my $meta = Class::MOP::get_metaclass_by_name($class)) {'."\n" + .' return $meta->new_object($class->BUILDARGS(@_));'."\n" .' }'."\n" ), ) @@ -130,20 +191,21 @@ sub _constructor_maker_for { } 1; +__END__ + =pod =encoding utf-8 =head1 NAME -Moo - Minimalist Object Orientation (with Moose compatiblity) +Moo - Minimalist Object Orientation (with Moose compatibility) =head1 SYNOPSIS package Cat::Food; use Moo; - use Sub::Quote; sub feed_lion { my $self = shift; @@ -161,16 +223,16 @@ Moo - Minimalist Object Orientation (with Moose compatiblity) isa => sub { die "Only SWEET-TREATZ supported!" unless $_[0] eq 'SWEET-TREATZ' }, -); + ); has pounds => ( is => 'rw', - isa => quote_sub q{ die "$_[0] is too much cat food!" unless $_[0] < 15 }, + isa => sub { die "$_[0] is too much cat food!" unless $_[0] < 15 }, ); 1; -and else where +And elsewhere: my $full = Cat::Food->new( taste => 'DELICIOUS.', @@ -184,57 +246,110 @@ and else where =head1 DESCRIPTION -This module is an extremely light-weight, high-performance L replacement. +This module is an extremely light-weight subset of L optimised for +rapid startup and "pay only for what you use". + It also avoids depending on any XS modules to allow simple deployments. The -name C is based on the idea that it provides almost -but not quite- two +name C is based on the idea that it provides almost -- but not quite -- two thirds of L. -Unlike C this module does not aim at full L compatibility. See -L for more details. +Unlike L this module does not aim at full compatibility with +L's surface syntax, preferring instead of provide full interoperability +via the metaclass inflation capabilities described in L. + +For a full list of the minor differences between L and L's surface +syntax, see L. =head1 WHY MOO EXISTS If you want a full object system with a rich Metaprotocol, L is already wonderful. +However, sometimes you're writing a command line script or a CGI script +where fast startup is essential, or code designed to be deployed as a single +file via L, or you're writing a CPAN module and you want it +to be usable by people with those constraints. + I've tried several times to use L but it's 3x the size of Moo and takes longer to load than most of my Moo based CGI scripts take to run. If you don't want L, you don't want "less metaprotocol" like L, -you want "as little as possible" - which means "no metaprotocol", which is +you want "as little as possible" -- which means "no metaprotocol", which is what Moo provides. -By Moo 1.0 I intend to have Moo's equivalent of L built in - -if Moose gets loaded, any Moo class or role will act as a Moose equivalent -if treated as such. +Better still, if you install and load L, we set up metaclasses for your +L classes and L roles, so you can use them in L code +without ever noticing that some of your codebase is using L. -Hence - Moo exists as its name - Minimal Object Orientation - with a pledge +Hence, Moo exists as its name -- Minimal Object Orientation -- with a pledge to make it smooth to upgrade to L when you need more than minimal features. -=head1 Moo and Moose - NEW, EXPERIMENTAL +=head1 MOO AND MOOSE If L detects L being loaded, it will automatically register metaclasses for your L and L packages, so you should be able -to use them in L code without it ever realising you aren't using +to use them in L code without anybody ever noticing you aren't using L everywhere. -Extending a L class or consuming a L should also work. +L will also create L for +classes and roles, so that C<< isa => 'MyClass' >> and C<< isa => 'MyRole' >> +work the same as for L classes and roles. + +Extending a L class or consuming a L will also work. + +So will extending a L class or consuming a L - but note +that we don't provide L metaclasses or metaroles so the other way +around doesn't work. This feature exists for L users porting to +L; enabling L users to use L classes is not a priority for us. This means that there is no need for anything like L for Moo -code - Moo and Moose code should simply interoperate without problem. +code - Moo and Moose code should simply interoperate without problem. To +handle L code, you'll likely need an empty Moo role or class consuming +or extending the L stuff since it doesn't register true L +metaclasses like L does. -However, these features are new as of 0.91.0 (0.091000) so while serviceable, -they are absolutely certain to not be 100% yet; please do report bugs. +If you want types to be upgraded to the L types, use +L and install the L library to +match the L library you're using - L will +load the L library and use that type for the newly created +metaclass. If you need to disable the metaclass creation, add: no Moo::sification; to your code before Moose is loaded, but bear in mind that this switch is -currently global and turns the mechanism off entirely, so don't put this -in library code, only in a top level script as a temporary measure while -you send a bug report. +currently global and turns the mechanism off entirely so don't put this +in library code. + +=head1 MOO AND CLASS::XSACCESSOR + +If a new enough version of L is available, it +will be used to generate simple accessors, readers, and writers for +a speed boost. Simple accessors are those without lazy defaults, +type checks/coercions, or triggers. Readers and writers generated +by L will behave slightly differently: they will +reject attempts to call them with the incorrect number of parameters. + +=head1 MOO VERSUS ANY::MOOSE + +L will load L normally, and L in a program using +L - which theoretically allows you to get the startup time of L +without disadvantaging L users. + +Sadly, this doesn't entirely work, since the selection is load order dependent +- L's metaclass inflation system explained above in L is +significantly more reliable. + +So if you want to write a CPAN module that loads fast or has only pure perl +dependencies but is also fully usable by L users, you should be using +L. + +For a full explanation, see the article +L which explains +the differing strategies in more detail and provides a direct example of +where L succeeds and L fails. =head1 IMPORTED METHODS @@ -267,6 +382,13 @@ passed to the constructor. This method should always return a hash reference of named options. +=head2 FOREIGNBUILDARGS + +If you are inheriting from a non-Moo class, the arguments passed to the parent +class constructor can be manipulated by defining a C method. +It will receive the same arguments as C, and should return a list +of arguments to pass to the parent class constructor. + =head2 BUILD Define a C method on your class and the constructor will automatically @@ -324,38 +446,98 @@ class. An error will be raised if these roles have conflicting methods. Declares an attribute for the class. + package Foo; + use Moo; + has 'attr' => ( + is => 'ro' + ); + + package Bar; + use Moo; + extends 'Foo'; + has '+attr' => ( + default => sub { "blah" }, + ); + +Using the C<+> notation, it's possible to override an attribute. + The options for C are as follows: =over 2 =item * is -B, must be C or C. Unsurprisingly, C generates an -accessor that will not respond to arguments; to be clear: a getter only. C -will create a perlish getter/setter. +B, may be C, C, C or C. + +C generates an accessor that dies if you attempt to write to it - i.e. +a getter only - by defaulting C to the name of the attribute. + +C generates a reader like C, but also sets C to 1 and +C to C<_build_${attribute_name}> to allow on-demand generated +attributes. This feature was my attempt to fix my incompetence when +originally designing C, and is also implemented by +L. There is, however, nothing to stop you +using C and C yourself with C or C - it's just that +this isn't generally a good idea so we don't provide a shortcut for it. + +C generates a reader like C, but also sets C to +C<_set_${attribute_name}> for attributes that are designed to be written +from inside of the class, but read-only from outside. +This feature comes from L. + +C generates a normal getter/setter by defaulting C to the +name of the attribute. =item * isa -Takes a coderef which is meant to validate the attribute. Unlike L Moo +Takes a coderef which is meant to validate the attribute. Unlike L, Moo does not include a basic type system, so instead of doing C<< isa => 'Num' >>, one should do - isa => quote_sub q{ + isa => sub { die "$_[0] is not a number!" unless looks_like_number $_[0] }, +Note that the return value is ignored, only whether the sub lives or +dies matters. + L +Since L does B run the C check before C if a coercion +subroutine has been supplied, C checks are not structural to your code +and can, if desired, be omitted on non-debug builds (although if this results +in an uncaught bug causing your program to break, the L authors guarantee +nothing except that you get to keep both halves). + +If you want L style named types, look at +L. + +To cause your C entries to be automatically mapped to named +L objects (rather than the default behaviour +of creating an anonymous type), set: + + $Moo::HandleMoose::TYPE_MAP{$isa_coderef} = sub { + require MooseX::Types::Something; + return MooseX::Types::Something::TypeName(); + }; + +Note that this example is purely illustrative; anything that returns a +L object or something similar enough to it to +make L happy is fine. + =item * coerce Takes a coderef which is meant to coerce the attribute. The basic idea is to do something like the following: - coerce => quote_sub q{ - $_[0] + 1 unless $_[0] % 2 + coerce => sub { + $_[0] % 2 ? $_[0] : $_[0] + 1 }, -Coerce does not require C to be defined. +Note that L will always fire your coercion: this is to permit +C entries to be used purely for bug trapping, whereas coercions are +always structural to your code. We do, however, apply any supplied C +check after the coercion has run to ensure that it returned a valid value. L @@ -378,38 +560,48 @@ Takes a hashref un => 'one', } -=item * trigger +=item * C Takes a coderef which will get called any time the attribute is set. This -includes the constructor. Coderef will be invoked against the object with the -new value as an argument. +includes the constructor, but not default or built values. Coderef will be +invoked against the object with the new value as an argument. + +If you set this to just C<1>, it generates a trigger which calls the +C<_trigger_${attr_name}> method on C<$self>. This feature comes from +L. Note that Moose also passes the old value, if any; this feature is not yet supported. L -=item * default +=item * C Takes a coderef which will get called with $self as its only argument to populate an attribute if no value is supplied to the constructor - or if the attribute is lazy, when the attribute is first retrieved if no value has yet been provided. +If a simple scalar is provided, it will be inlined as a string. Any non-code +reference (hash, array) will result in an error - for that case instead use +a code reference that returns the desired value. + Note that if your default is fired during new() there is no guarantee that other attributes have been populated yet so you should not rely on their existence. L -=item * predicate +=item * C Takes a method name which will return true if an attribute has a value. -A common example of this would be to call it C, implying that the -object has a C<$foo> set. +If you set this to just C<1>, the predicate is automatically named +C if your attribute's name does not start with an +underscore, or C<_has_${attr_name_without_the_underscore}> if it does. +This feature comes from L. -=item * builder +=item * C Takes a method name which will be called to create the attribute - functions exactly like default except that instead of calling @@ -420,43 +612,65 @@ Moo will call $self->$builder; -=item * clearer +The following features come from L: + +If you set this to just C<1>, the builder is automatically named +C<_build_${attr_name}>. + +If you set this to a coderef or code-convertible object, that variable will be +installed under C<$class::_build_${attr_name}> and the builder set to the same +name. + +=item * C Takes a method name which will clear the attribute. -=item * lazy +If you set this to just C<1>, the clearer is automatically named +C if your attribute's name does not start with an +underscore, or <_clear_${attr_name_without_the_underscore}> if it does. +This feature comes from L. + +=item * C B. Set this if you want values for the attribute to be grabbed lazily. This is usually a good idea if you have a L which requires another attribute to be set. -=item * required +=item * C B. Set this if the attribute must be passed on instantiation. -=item * reader +=item * C The value of this attribute will be the name of the method to get the value of the attribute. If you like Java style methods, you might set this to C -=item * writer +=item * C The value of this attribute will be the name of the method to set the value of the attribute. If you like Java style methods, you might set this to -C +C. -=item * weak_ref +=item * C B. Set this if you want the reference that the attribute contains to be weakened; use this when circular references are possible, which will cause leaks. -=item * init_arg +=item * C Takes the name of the key to look for at instantiation time of the object. A common use of this is to make an underscored attribute have a non-underscored initialization name. C means that passing the value in on instantiation +is ignored. + +=item * C + +Takes either a coderef or array of coderefs which is meant to transform the +given attributes specifications if necessary when upgrading to a Moose role or +class. You shouldn't need this by default, but is provided as a means of +possible extensibility. =back @@ -487,9 +701,43 @@ L allows us to create coderefs that are "inlineable," giving us a handy, XS-free speed boost. Any option that is L aware can take advantage of this. +To do this, you can write + + use Moo; + use Sub::Quote; + + has foo => ( + is => 'ro', + isa => quote_sub(q{ die "Not <3" unless $_[0] < 3 }) + ); + +which will be inlined as + + do { + local @_ = ($_[0]->{foo}); + die "Not <3" unless $_[0] < 3; + } + +or to avoid localizing @_, + + has foo => ( + is => 'ro', + isa => quote_sub(q{ my ($val) = @_; die "Not <3" unless $val < 3 }) + ); + +which will be inlined as + + do { + my ($val) = ($_[0]->{foo}); + die "Not <3" unless $val < 3; + } + +See L for more information, including how to pass lexical +captures that will also be compiled into the subroutine. + =head1 INCOMPATIBILITIES WITH MOOSE -There is no built in type system. C is verified with a coderef, if you +There is no built-in type system. C is verified with a coderef; if you need complex types, just make a library of coderefs, or better yet, functions that return quoted subs. L provides a similar API to L so that you can write @@ -501,7 +749,7 @@ API will encourage the use of other type systems as well, since it's probably the weakest part of Moose design-wise. C is not supported in core since the author considers it to be a -bad idea but may be supported by an extension in future. Meanwhile C or +bad idea and Moose best practices recommend avoiding it. Meanwhile C or C are more likely to be able to fulfill your needs. There is no meta object. If you need this level of complexity you wanted @@ -512,26 +760,44 @@ provide a metaprotocol. However, if you load L, then will return an appropriate metaclass pre-populated by L. -No support for C, C, C, or C - override can -be handled by around albeit with a little more typing, and the author considers -augment to be a bad idea. +No support for C, C, C, or C - the author +considers augment to be a bad idea, and override can be translated: + + override foo => sub { + ... + super(); + ... + }; + + around foo => sub { + my ($orig, $self) = (shift, shift); + ... + $self->$orig(@_); + ... + }; The C method is not provided by default. The author suggests loading L into C (via C for example) and using C<$obj-E$::Dwarn()> instead. -L only supports coderefs, because doing otherwise is usually a -mistake anyway. +L only supports coderefs and plain scalars, because passing a hash +or array reference as a default is almost always incorrect since the value is +then shared between all objects using that default. C is not supported; you are instead encouraged to use the -C 'lazy'> option supported by L and L. +C<< is => 'lazy' >> option supported by L and L. -C is not supported since the author considers it a bad idea. +C is not supported since the author considers it a bad idea and +it has been considered best practice to avoid it for some time. C will show up in a L metaclass created from your class -but is otherwise ignored. Then again, L ignors it as well, so this +but is otherwise ignored. Then again, L ignores it as well, so this is arguably not an incompatibility. +Since C does not require C to be defined but L does +require it, the metaclass inflation for coerce alone is a trifle insane +and if you attempt to subtype the result will almost certainly break. + Handling of warnings: when you C we enable FATAL warnings. The nearest similar invocation for L would be: @@ -568,11 +834,26 @@ Finally, Moose requires you to call at the end of your class to get an inlined (i.e. not horribly slow) constructor. Moo does it automatically the first time ->new is called -on your class. +on your class. (C is a no-op in Moo to ease migration.) + +An extension L exists to ease translating Moose packages +to Moo by providing a more Moose-like interface. =head1 SUPPORT -IRC: #web-simple on irc.perl.org +Users' IRC: #moose on irc.perl.org + +=for html (click for instant chatroom login) + +Development and contribution IRC: #web-simple on irc.perl.org + +=for html (click for instant chatroom login) + +Bugtracker: L + +Git repository: L + +Git web access: L =head1 AUTHOR @@ -598,6 +879,16 @@ doy - Jesse Luehrs (cpan:DOY) perigrin - Chris Prather (cpan:PERIGRIN) +Mithaldu - Christian Walde (cpan:MITHALDU) + +ilmari - Dagfinn Ilmari Mannsåker (cpan:ILMARI) + +tobyink - Toby Inkster (cpan:TOBYINK) + +haarg - Graham Knop (cpan:HAARG) + +mattp - Matt Phillips (cpan:MATTP) + =head1 COPYRIGHT Copyright (c) 2010-2011 the Moo L and L @@ -606,6 +897,6 @@ as listed above. =head1 LICENSE This library is free software and may be distributed under the same terms -as perl itself. +as perl itself. See L. =cut