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  );
  ...
  
  my $obj = MyObject->new( foo => 'Foozle' );
  print $obj->foo();
  
  $obj->bar('Barbados');
  print $obj->bar();
  
  $obj->my_list(0 => 'Foozle', 1 => 'Bang!');
  print $obj->my_list(1);
  
  $obj->my_index('broccoli' => 'Blah!', 'foo' => 'Fiddle');
  print $obj->my_index('foo');

=head1 DESCRIPTION

The Standard::Array suclass 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::Standard/"Calling Conventions"> for more information.

=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::Standard/"Declaration Syntax"> and L<Class::MakeMethods::Standard/"Parameter Syntax"> for more information.

=cut

package Class::MakeMethods::Standard::Array;

$VERSION = 1.000;
use strict;
use Class::MakeMethods::Standard '-isasubclass';
use Class::MakeMethods::Utility::ArraySplicer 'array_splicer';

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

=head2 Positional Accessors and %FIELDS

Each accessor method is assigned the next available array index at
which to store its value.

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

B<Warning>: 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 *

Has a reference to a sample item to copy. This defaults to a reference to an empty array, but you may override this with the C<'defaults' => I<array_ref>> method parameter. 

=item *

If called as a class method, makes a new array containing values from the sample item, 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.