view release on metacpan or  search on metacpan

MakeMethods/Basic/Array.pm  view on Meta::CPAN

  my $obj = MyObject->new( foo => 'Foozle' );
  
  # Scalar Accessor
  print $obj->foo();
  
  $obj->bar('Barbados');
  print $obj->bar();
  
  # Array accessor
  $obj->my_list(0 => 'Foozle', 1 => 'Bang!');
  print $obj->my_list(1);
  
  # Hash accessor
  $obj->my_index('broccoli' => 'Blah!', 'foo' => 'Fiddle');
  print $obj->my_index('foo');


=head1 DESCRIPTION

The Basic::Array subclass of MakeMethods provides a basic
constructor and accessors for blessed-array object instances.

=head2 Calling Conventions

When you C<use> this package, the method names you provide
as arguments cause subroutines to be generated and installed in
your module.

See L<Class::MakeMethods::Basic/"Calling Conventions"> for a summary, or L<Class::MakeMethods/"USAGE"> for full details.

=head2 Declaration Syntax

To declare methods, pass in pairs of a method-type name followed
by one or more method names. Valid method-type names for this
package are listed in L<"METHOD GENERATOR TYPES">.

See L<Class::MakeMethods::Basic/"Declaration Syntax"> for more
syntax information.

=cut

package Class::MakeMethods::Basic::Array;

$VERSION = 1.000;
use strict;
use Class::MakeMethods '-isasubclass';

########################################################################

=head2 About Positional Accessors

Each accessor method claims the next available spot in the array
to store its value in.

The mapping between method names and array positions is stored in
a hash named %FIELDS in the target package. When the first positional
accessor is defined for a package, its %FIELDS are initialized by
searching its inheritance tree.

B<Caution>: Subclassing packages that use positional accessors is
somewhat fragile, since you may end up with two distinct methods
assigned to the same position. Specific cases to avoid are:

=over 4

=item *

If you inherit from more than one class with positional accessors,
the positions used by the two sets of methods will overlap.

=item *

If your superclass adds additional positional accessors after you
declare your first, they will overlap yours.

=back

=cut

sub _array_index {
  my $class = shift;
  my $name = shift;
  no strict;
  local $^W = 0;
  if ( ! scalar %{$class . "::FIELDS"} ) {
    my @classes = @{$class . "::ISA"};
    my @fields;
    while ( @classes ) {
      my $superclass = shift @classes;
      if ( scalar %{$superclass . "::FIELDS"} ) {
	push @fields, %{$superclass . "::FIELDS"};
      } else {
	unshift @classes, @{$superclass . "::ISA"}
      }
    }
    %{$class . "::FIELDS"} = @fields
  }
  my $field_hash = \%{$class . "::FIELDS"};
  $field_hash->{$name} or $field_hash->{$name} = scalar keys %$field_hash
}

########################################################################

=head1 METHOD GENERATOR TYPES

=head2 new - Constructor

For each method name passed, returns a subroutine with the following characteristics:

=over 4

=item *

If called as a class method, makes a new array and blesses it into that class.

=item *

If called on an array-based instance, makes a copy of it and blesses the copy into the same class as the original instance.

=item *