X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FMouse%2FMeta%2FAttribute.pm;h=54fc2b57bd4e6e8e2596f366f7ae2e0c939f4970;hb=HEAD;hp=e87dec4cf7f449df8867130a90386a7f9346fa12;hpb=06f35b369e6064421a9a4e095d0c9d8eef008f87;p=gitmo%2FMouse.git

diff --git a/lib/Mouse/Meta/Attribute.pm b/lib/Mouse/Meta/Attribute.pm
index e87dec4..54fc2b5 100644
--- a/lib/Mouse/Meta/Attribute.pm
+++ b/lib/Mouse/Meta/Attribute.pm
@@ -1,217 +1,111 @@
 package Mouse::Meta::Attribute;
-use strict;
-use warnings;
+use Mouse::Util qw(:meta); # enables strict and warnings
 
 use Carp ();
 
-use Mouse::Util qw(:meta);
-
 use Mouse::Meta::TypeConstraint;
-use Mouse::Meta::Method::Accessor;
-
-sub _process_options{
-    my($class, $name, $args) = @_;
-
-
-    # XXX: for backward compatibility (with method modifiers)
-    if($class->can('canonicalize_args') != \&canonicalize_args){
-        %{$args} = $class->canonicalize_args($name, %{$args});
-    }
-
-    # taken from Class::MOP::Attribute::new
-
-    defined($name)
-        or $class->throw_error('You must provide a name for the attribute');
-
-    if(!exists $args->{init_arg}){
-        $args->{init_arg} = $name;
-    }
-
-    # 'required' requires eigher 'init_arg', 'builder', or 'default'
-    my $can_be_required = defined( $args->{init_arg} );
-
-    if(exists $args->{builder}){
-        # XXX:
-        # Moose refuses a CODE ref builder, but Mouse doesn't for backward compatibility
-        # This feature will be changed in a future. (gfx)
-        $class->throw_error('builder must be a defined scalar value which is a method name')
-            #if ref $args->{builder} || !defined $args->{builder};
-            if !defined $args->{builder};
-
-        $can_be_required++;
-    }
-    elsif(exists $args->{default}){
-        if(ref $args->{default} && ref($args->{default}) ne 'CODE'){
-            $class->throw_error("References are not allowed as default values, you must "
-                              . "wrap the default of '$name' in a CODE reference (ex: sub { [] } and not [])");
-        }
-        $can_be_required++;
-    }
 
-    if( $args->{required} && !$can_be_required ) {
-        $class->throw_error("You cannot have a required attribute ($name) without a default, builder, or an init_arg");
-    }
+my %valid_options = map { $_ => undef } (
+  'accessor',
+  'auto_deref',
+  'builder',
+  'clearer',
+  'coerce',
+  'default',
+  'documentation',
+  'does',
+  'handles',
+  'init_arg',
+  'insertion_order',
+  'is',
+  'isa',
+  'lazy',
+  'lazy_build',
+  'name',
+  'predicate',
+  'reader',
+  'required',
+  'traits',
+  'trigger',
+  'type_constraint',
+  'weak_ref',
+  'writer',
+
+  # internally used
+  'associated_class',
+  'associated_methods',
+  '__METACLASS__',
+
+  # Moose defines, but Mouse doesn't
+  #'definition_context',
+  #'initializer',
+
+  # special case for AttributeHelpers
+  'provides',
+  'curries',
+);
+
+our @CARP_NOT = qw(Mouse::Meta::Class);
 
-    # taken from Mouse::Meta::Attribute->new and _process_args->
+sub new {
+    my $class = shift;
+    my $name  = shift;
 
-    if(exists $args->{is}){
-        my $is = $args->{is};
+    my $args  = $class->Mouse::Object::BUILDARGS(@_);
 
-        if($is eq 'ro'){
-            $args->{reader} ||= $name;
-        }
-        elsif($is eq 'rw'){
-            if(exists $args->{writer}){
-                $args->{reader} ||= $name;
-             }
-             else{
-                $args->{accessor} ||= $name;
-             }
-        }
-        elsif($is eq 'bare'){
-            # do nothing, but don't complain (later) about missing methods
-        }
-        else{
-            $is = 'undef' if !defined $is;
-            $class->throw_error("I do not understand this option (is => $is) on attribute ($name)");
-        }
-    }
+    $class->_process_options($name, $args);
 
-    my $tc;
-    if(exists $args->{isa}){
-        $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_isa_type_constraint($args->{isa});
-    }
-    elsif(exists $args->{does}){
-        # TODO
-        # $args->{type_constraint} = Mouse::Util::TypeConstraints::find_or_create_does_type_constraint($args->{does});
-    }
-    $tc = $args->{type_constraint};
+    $args->{name} = $name;
 
-    if($args->{coerce}){
-        defined($tc)
-            || $class->throw_error("You cannot have coercion without specifying a type constraint on attribute ($name)");
+    # check options
+    # (1) known by core
+    my @bad = grep{ !exists $valid_options{$_} } keys %{$args};
 
-        $args->{weak_ref}
-            && $class->throw_error("You cannot have a weak reference to a coerced value on attribute ($name)");
+    # (2) known by subclasses
+    if(@bad && $class ne __PACKAGE__){
+        my %valid_attrs = (
+            map { $_ => undef }
+            grep { defined }
+            map { $_->init_arg() }
+            $class->meta->get_all_attributes()
+        );
+        @bad = grep{ !exists $valid_attrs{$_} } @bad;
     }
 
-    if ($args->{lazy_build}) {
-        exists($args->{default})
-            && $class->throw_error("You can not use lazy_build and default for the same attribute ($name)");
-
-        $args->{lazy}      = 1;
-        $args->{builder} ||= "_build_${name}";
-        if ($name =~ /^_/) {
-            $args->{clearer}   ||= "_clear${name}";
-            $args->{predicate} ||= "_has${name}";
-        }
-        else {
-            $args->{clearer}   ||= "clear_${name}";
-            $args->{predicate} ||= "has_${name}";
-        }
+    # (3) bad options found
+    if(@bad){
+        Carp::carp(
+            "Found unknown argument(s) passed to '$name' attribute constructor in '$class': "
+            . Mouse::Util::english_list(@bad));
     }
 
-    if ($args->{auto_deref}) {
-        defined($tc)
-            || $class->throw_error("You cannot auto-dereference without specifying a type constraint on attribute ($name)");
-
-        ( $tc->is_a_type_of('ArrayRef') || $tc->is_a_type_of('HashRef') )
-            || $class->throw_error("You cannot auto-dereference anything other than a ArrayRef or HashRef on attribute ($name)");
-    }
-
-    if (exists $args->{trigger}) {
-        ('CODE' eq ref $args->{trigger})
-            || $class->throw_error("Trigger must be a CODE ref on attribute ($name)");
-    }
-
-    if ($args->{lazy}) {
-        (exists $args->{default} || defined $args->{builder})
-            || $class->throw_error("You cannot have lazy attribute ($name) without specifying a default value for it");
+    my $self = bless $args, $class;
+    if($class ne __PACKAGE__){
+        $class->meta->_initialize_object($self, $args);
     }
-
-    return;
+    return $self;
 }
 
-sub new {
-    my $class = shift;
-    my $name  = shift;
-
-    my %args  = (@_ == 1) ? %{ $_[0] } : @_;
-
-    $class->_process_options($name, \%args);
-
-    $args{name} = $name;
-
-    my $instance = bless \%args, $class;
-
-    # extra attributes
-    if($class ne __PACKAGE__){
-        $class->meta->_initialize_instance($instance,\%args);
-    }
+sub has_read_method   { $_[0]->has_reader || $_[0]->has_accessor }
+sub has_write_method  { $_[0]->has_writer || $_[0]->has_accessor }
 
-# XXX: there is no fast way to check attribute validity
-#    my @bad = ...;
-#    if(@bad){
-#        @bad = sort @bad;
-#        Carp::cluck("Found unknown argument(s) passed to '$name' attribute constructor in '$class': @bad");
-#    }
+sub get_read_method   { $_[0]->reader || $_[0]->accessor }
+sub get_write_method  { $_[0]->writer || $_[0]->accessor }
 
-    return $instance;
+sub get_read_method_ref{
+    my($self) = @_;
+    return $self->{_mouse_cache_read_method_ref}
+        ||= $self->_get_accessor_method_ref('get_read_method', '_generate_reader');
 }
 
-# readers
-
-sub name                 { $_[0]->{name}                   }
-sub associated_class     { $_[0]->{associated_class}       }
-
-sub accessor             { $_[0]->{accessor}               }
-sub reader               { $_[0]->{reader}                 }
-sub writer               { $_[0]->{writer}                 }
-sub predicate            { $_[0]->{predicate}              }
-sub clearer              { $_[0]->{clearer}                }
-sub handles              { $_[0]->{handles}                }
-
-sub _is_metadata         { $_[0]->{is}                     }
-sub is_required          { $_[0]->{required}               }
-sub default              { $_[0]->{default}                }
-sub is_lazy              { $_[0]->{lazy}                   }
-sub is_lazy_build        { $_[0]->{lazy_build}             }
-sub is_weak_ref          { $_[0]->{weak_ref}               }
-sub init_arg             { $_[0]->{init_arg}               }
-sub type_constraint      { $_[0]->{type_constraint}        }
-
-sub trigger              { $_[0]->{trigger}                }
-sub builder              { $_[0]->{builder}                }
-sub should_auto_deref    { $_[0]->{auto_deref}             }
-sub should_coerce        { $_[0]->{coerce}                 }
-
-sub get_read_method      { $_[0]->{reader} || $_[0]->{accessor} }
-sub get_write_method     { $_[0]->{writer} || $_[0]->{accessor} }
-
-# predicates
-
-sub has_accessor         { exists $_[0]->{accessor}        }
-sub has_reader           { exists $_[0]->{reader}          }
-sub has_writer           { exists $_[0]->{writer}          }
-sub has_predicate        { exists $_[0]->{predicate}       }
-sub has_clearer          { exists $_[0]->{clearer}         }
-sub has_handles          { exists $_[0]->{handles}         }
-
-sub has_default          { exists $_[0]->{default}         }
-sub has_type_constraint  { exists $_[0]->{type_constraint} }
-sub has_trigger          { exists $_[0]->{trigger}         }
-sub has_builder          { exists $_[0]->{builder}         }
-
-sub has_read_method      { exists $_[0]->{reader} || exists $_[0]->{accessor} }
-sub has_write_method     { exists $_[0]->{writer} || exists $_[0]->{accessor} }
-
-sub _create_args {
-    $_[0]->{_create_args} = $_[1] if @_ > 1;
-    $_[0]->{_create_args}
+sub get_write_method_ref{
+    my($self) = @_;
+    return $self->{_mouse_cache_write_method_ref}
+        ||= $self->_get_accessor_method_ref('get_write_method', '_generate_writer');
 }
 
 sub interpolate_class{
-    my($class, $name, $args) = @_;
+    my($class, $args) = @_;
 
     if(my $metaclass = delete $args->{metaclass}){
         $class = Mouse::Util::resolve_metaclass_alias( Attribute => $metaclass );
@@ -244,117 +138,109 @@ sub interpolate_class{
     return( $class, @traits );
 }
 
-sub canonicalize_args{
-    my ($self, $name, %args) = @_;
+sub verify_against_type_constraint {
+    my ($self, $value) = @_;
 
-    Carp::cluck("$self->canonicalize_args has been deprecated."
-        . "Use \$self->_process_options instead.")
-            if _MOUSE_VERBOSE;
+    my $type_constraint = $self->{type_constraint};
+    return 1 if !$type_constraint;
+    return 1 if $type_constraint->check($value);
 
-    return %args;
+    $self->_throw_type_constraint_error($value, $type_constraint);
 }
 
-sub create {
-    my ($self, $class, $name, %args) = @_;
+sub _throw_type_constraint_error {
+    my($self, $value, $type) = @_;
 
-    Carp::cluck("$self->create has been deprecated."
-        . "Use \$meta->add_attribute and \$attr->install_accessors instead.")
-            if _MOUSE_VERBOSE;
-
-    # noop
-    return $self;
+    $self->throw_error(
+        sprintf q{Attribute (%s) does not pass the type constraint because: %s},
+            $self->name,
+            $type->get_message($value),
+    );
 }
 
-sub _coerce_and_verify {
-    my($self, $value, $instance) = @_;
-
-    my $type_constraint = $self->{type_constraint};
+sub illegal_options_for_inheritance {
+    return qw(reader writer accessor clearer predicate);
+}
 
-    return $value if !$type_constraint;
+sub clone_and_inherit_options{
+    my $self = shift;
+    my $args = $self->Mouse::Object::BUILDARGS(@_);
 
-    if ($self->should_coerce && $type_constraint->has_coercion) {
-        $value = $type_constraint->coerce($value);
+    foreach my $illegal($self->illegal_options_for_inheritance) {
+        if(exists $args->{$illegal} and exists $self->{$illegal}) {
+            $self->throw_error("Illegal inherited option: $illegal");
+        }
     }
 
-    return $value if $type_constraint->check($value);
-
-    $self->verify_against_type_constraint($value);
+    foreach my $name(keys %{$self}){
+        if(!exists $args->{$name}){
+            $args->{$name} = $self->{$name}; # inherit from self
+        }
+    }
 
-    return $value;
-}
+    my($attribute_class, @traits) = ref($self)->interpolate_class($args);
+    $args->{traits} = \@traits if @traits;
 
-sub verify_against_type_constraint {
-    my ($self, $value) = @_;
+    # remove temporary caches
+    foreach my $attr(keys %{$args}){
+        if($attr =~ /\A _mouse_cache_/xms){
+            delete $args->{$attr};
+        }
+    }
 
-    my $type_constraint = $self->{type_constraint};
-    return 1 if !$type_constraint;;
-    return 1 if $type_constraint->check($value);
+    # remove default if lazy_build => 1
+    if($args->{lazy_build}) {
+        delete $args->{default};
+    }
 
-    $self->verify_type_constraint_error($self->name, $value, $type_constraint);
+    return $attribute_class->new($self->name, $args);
 }
 
-sub verify_type_constraint_error {
-    my($self, $name, $value, $type) = @_;
-    $self->throw_error("Attribute ($name) does not pass the type constraint because: " . $type->get_message($value));
-}
 
-sub coerce_constraint { ## my($self, $value) = @_;
-    my $type = $_[0]->{type_constraint}
-        or return $_[1];
-    return Mouse::Util::TypeConstraints->typecast_constraints($_[0]->associated_class->name, $type, $_[1]);
-}
+sub _get_accessor_method_ref {
+    my($self, $type, $generator) = @_;
 
-sub _canonicalize_handles {
-    my $self    = shift;
-    my $handles = shift;
+    my $metaclass = $self->associated_class
+        || $self->throw_error('No asocciated class for ' . $self->name);
 
-    if (ref($handles) eq 'HASH') {
-        return %$handles;
+    my $accessor = $self->$type();
+    if($accessor){
+        return $metaclass->get_method_body($accessor);
     }
-    elsif (ref($handles) eq 'ARRAY') {
-        return map { $_ => $_ } @$handles;
-    }
-    else {
-        $self->throw_error("Unable to canonicalize the 'handles' option with $handles");
+    else{
+        return $self->accessor_metaclass->$generator($self, $metaclass);
     }
 }
 
-sub clone_and_inherit_options{
-    my $self = shift;
-    my $name = shift;
-
-    return ref($self)->new($name, %{$self}, (@_ == 1) ? %{$_[0]} : @_);
+sub set_value {
+    my($self, $object, $value) = @_;
+    return $self->get_write_method_ref()->($object, $value);
 }
 
-sub clone_parent {
-    my $self  = shift;
-    my $class = shift;
-    my $name  = shift;
-    my %args  = ($self->get_parent_args($class, $name), @_);
+sub get_value {
+    my($self, $object) = @_;
+    return $self->get_read_method_ref()->($object);
+}
 
-    Carp::cluck("$self->clone_parent has been deprecated."
-        . "Use \$meta->add_attribute and \$attr->install_accessors instead.")
-        if _MOUSE_VERBOSE;
+sub has_value {
+    my($self, $object) = @_;
+    my $accessor_ref = $self->{_mouse_cache_predicate_ref}
+        ||= $self->_get_accessor_method_ref('predicate', '_generate_predicate');
 
-    $self->clone_and_inherited_args($class, $name, %args);
+    return $accessor_ref->($object);
 }
 
-sub get_parent_args {
-    my $self  = shift;
-    my $class = shift;
-    my $name  = shift;
-
-    for my $super ($class->linearized_isa) {
-        my $super_attr = $super->can("meta") && $super->meta->get_attribute($name)
-            or next;
-        return %{ $super_attr->_create_args };
-    }
+sub clear_value {
+    my($self, $object) = @_;
+    my $accessor_ref = $self->{_mouse_cache_crealer_ref}
+        ||= $self->_get_accessor_method_ref('clearer', '_generate_clearer');
 
-    $self->throw_error("Could not find an attribute by the name of '$name' to inherit from");
+    return $accessor_ref->($object);
 }
 
 sub associate_method{
-    my ($attribute, $method) = @_;
+    #my($attribute, $method_name) = @_;
+    my($attribute) = @_;
     $attribute->{associated_methods}++;
     return;
 }
@@ -362,41 +248,114 @@ sub associate_method{
 sub install_accessors{
     my($attribute) = @_;
 
-    my $metaclass       = $attribute->{associated_class};
+    my $metaclass      = $attribute->associated_class;
+    my $accessor_class = $attribute->accessor_metaclass;
 
-    foreach my $type(qw(accessor reader writer predicate clearer handles)){
+    foreach my $type(qw(accessor reader writer predicate clearer)){
         if(exists $attribute->{$type}){
-            my $installer    = '_install_' . $type;
+            my $generator = '_generate_' . $type;
+            my $code      = $accessor_class->$generator($attribute, $metaclass);
+            my $name      = $attribute->{$type};
+# TODO: do something for compatibility
+#            if( $metaclass->name->can($name) ) {
+#                my $t = $metaclass->has_method($name) ? 'method' : 'function';
+#                Carp::cluck("You are overwriting a locally defined $t"
+#                    . " ($name) with an accessor");
+#            }
+            $metaclass->add_method($name => $code);
+            $attribute->associate_method($name);
+        }
+    }
 
-            Mouse::Meta::Method::Accessor->$installer($attribute, $attribute->{$type}, $metaclass);
+    # install delegation
+    if(exists $attribute->{handles}){
+        my %handles = $attribute->_canonicalize_handles();
+        while(my($handle, $method_to_call) = each %handles){
+            next if Mouse::Object->can($handle);
 
-            $attribute->{associated_methods}++;
+            if($metaclass->has_method($handle)) {
+                $attribute->throw_error("You cannot overwrite a locally defined method ($handle) with a delegation");
+            }
+
+            $metaclass->add_method($handle =>
+                $attribute->_make_delegation_method(
+                    $handle, $method_to_call));
+
+            $attribute->associate_method($handle);
         }
     }
 
-    if($attribute->can('create') != \&create){
-        # backword compatibility
-        $attribute->create($metaclass, $attribute->name, %{$attribute});
+    return;
+}
+
+sub delegation_metaclass() { ## no critic
+    'Mouse::Meta::Method::Delegation'
+}
+
+sub _canonicalize_handles {
+    my($self) = @_;
+    my $handles = $self->{handles};
+
+    my $handle_type = ref $handles;
+    if ($handle_type eq 'HASH') {
+        return %$handles;
+    }
+    elsif ($handle_type eq 'ARRAY') {
+        return map { $_ => $_ } @$handles;
+    }
+    elsif ($handle_type eq 'Regexp') {
+        my $meta = $self->_find_delegate_metaclass();
+        return map  { $_ => $_ }
+               grep { /$handles/ }
+                   Mouse::Util::is_a_metarole($meta)
+                        ? $meta->get_method_list
+                        : $meta->get_all_method_names;
+    }
+    elsif ($handle_type eq 'CODE') {
+        return $handles->( $self, $self->_find_delegate_metaclass() );
+    }
+    else {
+        $self->throw_error("Unable to canonicalize the 'handles' option with $handles");
     }
+}
 
-    return;
+sub _find_delegate_metaclass {
+    my($self) = @_;
+    my $meta;
+    if($self->{isa}) {
+        $meta = Mouse::Meta::Class->initialize("$self->{isa}");
+    }
+    elsif($self->{does}) {
+        $meta = Mouse::Util::get_metaclass_by_name("$self->{does}");
+    }
+    defined($meta) or $self->throw_error(
+        "Cannot find delegate metaclass for attribute " . $self->name);
+    return $meta;
 }
 
-sub throw_error{
-    my $self = shift;
 
-    my $metaclass = (ref $self && $self->associated_class) || 'Mouse::Meta::Class';
-    $metaclass->throw_error(@_, depth => 1);
+sub _make_delegation_method {
+    my($self, $handle, $method_to_call) = @_;
+    return Mouse::Util::load_class($self->delegation_metaclass)
+        ->_generate_delegation($self, $handle, $method_to_call);
 }
 
 1;
-
 __END__
 
 =head1 NAME
 
 Mouse::Meta::Attribute - The Mouse attribute metaclass
 
+=head1 VERSION
+
+This document describes Mouse version 0.95
+
+=head1 DESCRIPTION
+
+This is a meta object protocol for Mouse attributes,
+which is a subset of Moose::Meta::Attribute.
+
 =head1 METHODS
 
 =head2 C<< new(%options) -> Mouse::Meta::Attribute >>
@@ -503,12 +462,12 @@ is equivalent to this:
 
 =back
 
-=head2 C<< associate_method(Method) >>
+=head2 C<< associate_method(MethodName) >>
 
 Associates a method with the attribute. Typically, this is called internally
 when an attribute generates its accessors.
 
-Currently the argument I<Method> is ignored in Mouse.
+Currently the argument I<MethodName> is ignored in Mouse.
 
 =head2 C<< verify_against_type_constraint(Item) -> TRUE | ERROR >>
 
@@ -520,6 +479,15 @@ on success, otherwise C<confess>es.
 Creates a new attribute in the owner class, inheriting options from parent classes.
 Accessors and helper methods are installed. Some error checking is done.
 
+=head2 C<< get_read_method_ref >>
+
+=head2 C<< get_write_method_ref >>
+
+Returns the subroutine reference of a method suitable for reading or
+writing the attribute's value in the associated class. These methods
+always return a subroutine reference, regardless of whether or not the
+attribute is read- or write-only.
+
 =head1 SEE ALSO
 
 L<Moose::Meta::Attribute>