use MRO::Compat;
use Carp 'confess';
-use Scalar::Util 'weaken', 'reftype', 'blessed';
+use Scalar::Util 'weaken', 'isweak', 'reftype', 'blessed';
+use Data::OptList;
use Try::Tiny;
use Class::MOP::Mixin::AttributeCore;
*check_package_cache_flag = \&mro::get_pkg_gen;
}
-our $VERSION = '1.00';
+our $VERSION = '1.10';
our $XS_VERSION = $VERSION;
$VERSION = eval $VERSION;
our $AUTHORITY = 'cpan:STEVAN';
require XSLoader;
XSLoader::load( __PACKAGE__, $XS_VERSION );
-
{
# Metaclasses are singletons, so we cache them here.
# there is no need to worry about destruction though
sub get_metaclass_by_name { $METAS{$_[0]} }
sub store_metaclass_by_name { $METAS{$_[0]} = $_[1] }
sub weaken_metaclass { weaken($METAS{$_[0]}) }
+ sub metaclass_is_weak { isweak($METAS{$_[0]}) }
sub does_metaclass_exist { exists $METAS{$_[0]} && defined $METAS{$_[0]} }
sub remove_metaclass_by_name { delete $METAS{$_[0]}; return }
}
sub load_first_existing_class {
- my @classes = @_
+ my $classes = Data::OptList::mkopt(\@_)
or return;
- foreach my $class (@classes) {
- unless ( _is_valid_class_name($class) ) {
- my $display = defined($class) ? $class : 'undef';
+ foreach my $class (@{ $classes }) {
+ my $name = $class->[0];
+ unless ( _is_valid_class_name($name) ) {
+ my $display = defined($name) ? $name : 'undef';
confess "Invalid class name ($display)";
}
}
my $found;
my %exceptions;
- for my $class (@classes) {
- my $file = _class_to_pmfile($class);
+ for my $class (@{ $classes }) {
+ my ($name, $options) = @{ $class };
- return $class if is_class_loaded($class);;
+ if ($options) {
+ return $name if is_class_loaded($name, $options);
+ if (is_class_loaded($name)) {
+ # we already know it's loaded and too old, but we call
+ # ->VERSION anyway to generate the exception for us
+ $name->VERSION($options->{-version});
+ }
+ }
+ else {
+ return $name if is_class_loaded($name);
+ }
- return $class if try {
+ my $file = _class_to_pmfile($name);
+ return $name if try {
local $SIG{__DIE__};
require $file;
+ $name->VERSION($options->{-version})
+ if defined $options->{-version};
return 1;
}
catch {
unless (/^Can't locate \Q$file\E in \@INC/) {
- confess "Couldn't load class ($class) because: $_";
+ confess "Couldn't load class ($name) because: $_";
}
return;
};
}
- if ( @classes > 1 ) {
- confess "Can't locate any of @classes in \@INC (\@INC contains: @INC).";
+ if ( @{ $classes } > 1 ) {
+ my @list = map { $_->[0] } @{ $classes };
+ confess "Can't locate any of @list in \@INC (\@INC contains: @INC).";
} else {
- confess "Can't locate " . _class_to_pmfile($classes[0]) . " in \@INC (\@INC contains: @INC).";
+ confess "Can't locate " . _class_to_pmfile($classes->[0]->[0]) . " in \@INC (\@INC contains: @INC).";
}
}
sub load_class {
- load_first_existing_class($_[0]);
+ load_first_existing_class($_[0], ref $_[1] ? $_[1] : ());
# This is done to avoid breaking code which checked the return value. Said
# code is dumb. The return value was _always_ true, since it dies on
))
);
-Class::MOP::Method->meta->add_method('clone' => sub {
- my $self = shift;
- my $clone = $self->meta->clone_object($self, @_);
- $clone->_set_original_method($self);
- return $clone;
-});
-
## --------------------------------------------------------
## Class::MOP::Method::Wrapped
),
);
+## --------------------------------------------------------
+## Class::MOP::Object
+
+# need to replace the meta method there with a real meta method object
+Class::MOP::Object->meta->_add_meta_method('meta');
+
+## --------------------------------------------------------
+## Class::MOP::Mixin
+
+# need to replace the meta method there with a real meta method object
+Class::MOP::Mixin->meta->_add_meta_method('meta');
+
require Class::MOP::Deprecated unless our $no_deprecated;
# we need the meta instance of the meta instance to be created now, in order
Class::MOP::Method::Accessor
Class::MOP::Method::Constructor
Class::MOP::Method::Wrapped
+
+ Class::MOP::Method::Meta
/;
$_->meta->make_immutable(
| A |<----| B |
+---------+ +---------+
+In actuality, I<all> of a class's metaclasses must be compatible,
+not just the class metaclass. That includes the instance, attribute,
+and method metaclasses, as well as the constructor and destructor
+classes.
+
+C<Class::MOP> will attempt to fix some simple types of
+incompatibilities. If all the metaclasses for the parent class are
+I<subclasses> of the child's metaclasses then we can simply replace
+the child's metaclasses with the parent's. In addition, if the child
+is missing a metaclass that the parent has, we can also just make the
+child use the parent's metaclass.
+
As I said this is a highly esoteric topic and one you will only run
into if you do a lot of subclassing of L<Class::MOP::Class>. If you
are interested in why this is an issue see the paper I<Uniform and
=over 4
-=item B<Class::MOP::load_class($class_name)>
+=item B<Class::MOP::load_class($class_name, \%options?)>
This will load the specified C<$class_name>, if it is not already
loaded (as reported by C<is_class_loaded>). This function can be used
If the module cannot be loaded, an exception is thrown.
+You can pass a hash reference with options as second argument. The
+only option currently recognised is C<-version>, which will ensure
+that the loaded class has at least the required version.
+
+See also L</Class Loading Options>.
+
For historical reasons, this function explicitly returns a true value.
-=item B<Class::MOP::is_class_loaded($class_name)>
+=item B<Class::MOP::is_class_loaded($class_name, \%options?)>
Returns a boolean indicating whether or not C<$class_name> has been
loaded.
cause most of the rest of the core L<IO> modules to falsely report
having been loaded, due to the way the base L<IO> module works.
+You can pass a hash reference with options as second argument. The
+only option currently recognised is C<-version>, which will ensure
+that the loaded class has at least the required version.
+
+See also L</Class Loading Options>.
+
=item B<Class::MOP::get_code_info($code)>
This function returns two values, the name of the package the C<$code>
=item B<Class::MOP::load_first_existing_class(@class_names)>
+=item B<Class::MOP::load_first_existing_class($classA, \%optionsA?, $classB, ...)>
+
B<NOTE: DO NOT USE THIS FUNCTION, IT IS FOR INTERNAL USE ONLY!>
Given a list of class names, this function will attempt to load each
If it finds a class it can load, it will return that class' name. If
none of the classes can be loaded, it will throw an exception.
+Additionally, you can pass a hash reference with options after each
+class name. Currently, only C<-version> is recognised and will ensure
+that the loaded class has at least the required version. If the class
+version is not sufficient, an exception will be raised.
+
+See also L</Class Loading Options>.
+
=back
=head2 Metaclass cache functions
function will weaken the reference to the metaclass stored
in C<$name>.
+=item B<Class::MOP::metaclass_is_weak($name)>
+
+Returns true if the metaclass for C<$name> has been weakened
+(via C<weaken_metaclass>).
+
=item B<Class::MOP::does_metaclass_exist($name)>
This will return true of there exists a metaclass stored in the
=back
+=head2 Class Loading Options
+
+=over 4
+
+=item -version
+
+Can be used to pass a minimum required version that will be checked
+against the class version after it was loaded.
+
+=back
+
=head1 SEE ALSO
=head2 Books
=item L<http://svn.openfoundry.org/pugs/misc/Perl-MetaModel/>
-=item L<http://svn.openfoundry.org/pugs/perl5/Perl6-ObjectSpace>
+=item L<http://github.com/perl6/p5-modules/tree/master/Perl6-ObjectSpace/>
=back
projects / gitmo/Class-MOP.git / blobdiff