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If the basic attribute B<id> is sweetened with C<auto_id>, the instance
is automatically assigned a UUID - see L<Data::UUID>.

The resulting B<id> is something like C<ECDAEFD4-9247-11DE-9343-7794CBAD412D>.

=item auto_inc

   has id  => ( auto_inc => true, ... );
   has +id => ( auto_inc => true, ... );

If the basic attribute B<id> is sweetened with C<auto_inc>, the
instance is automatically assigned a sequential number: I<highest used
id> + 1, where I<highest used id> = 0 in an empty cemetery.

=back

See L<Frost::Meta::Attribute>

=head1 The Four Commandments of Frost

=head2 Thou shalt absolve no other Moose before Locum

Frost can only store L<Moose> objects, more precisely: objects inheriting
from L<Frost::Locum>.

This does not mean, that each of your old classes must now use
Frost instead of L<Moose>. Migrating is easily possible by
creating or changing a base class from C<use Moose> to C<use
Frost> - i.e.

   package My::BaseFoo;
   # use Moose;
   use Frost;

   no Frost;
   __PACKAGE__->meta->make_immutable();   #  mutable is VERBOTEN

   package My::Foo;
   use Moose;
   extends 'My::BaseFoo';

   has my_attr      => ( ... );

   no Moose;
   __PACKAGE__->meta->make_immutable();   #  mutable is VERBOTEN

Thus My::Foo and all inheriting classes can be defined the usual L<Moose>
way. The class My::BaseFoo inherits from Frost::Locum, pulling
in all its persistence stuff.

=head2 Thou shalt honor immutability

While applying L<Moose>' tests for Frost it appeared, that reblessing an
object - i.e. because of applying a role at run-time - creates mutable
objects blessed in an anonymous class. This destroys the silence/evoke
mechanism, which depends on the real classname.

So reblessing as well as make_mutable is VERBOTEN.

=head2 Thou shalt not weaken thy reference

Due to Frost's proxy algorithm there is no need for weak references.
See L</MOTIVATION>.

=head2 Thou shalt not create or load objects without an id and thy asylum

To create a new frostable object you must always say:

   my $foo = Foo->new ( id => 'a_unique_id', asylum => $asylum, an_attr => ..., another_attr => ... );

   $remembered_id   = $foo->id;

And to reload a frosted object just say:

   my $foo = Foo->new ( id => $remembered_id, asylum => $asylum );   #   other params ignored

Or use the Asylum API - a matter of taste:

   my $remembered_id   = 'a_unique_id';

   my $foo = $asylum->silence ( 'Foo', $remembered_id, an_attr => ..., another_attr => ... );

   # later...

   my $foo = $asylum->evoke ( 'Foo', $remembered_id );   #   other params ignored

If the C<id> is defined with C<auto_id> or C<auto_inc>, Asylum is creating a mantra for you - i.e.:

   package Bar;
   ...
   has id ( auto_id => 1 );
   ...

   # Create and silence without id:
   #
   my $bar    = Bar->new ( asylum => $asylum, an_attr => ..., another_attr => ... );

   my $bar_id = $bar->id;   # something like ECDAEFD4-9247-11DE-9343-7794CBAD412D

   # Evoke with id:
   #
   my $bar    = Bar->new ( id => $bar_id, asylum => $asylum );

=head1 TODO

Docs, docs, docs...

=head1 GETTING HELP

I'm reading the L<Moose> mailing list frequently, so please ask your
questions there.

The mailing list is L<moose@perl.org>. You must be subscribed to send
a message. To subscribe, send an empty message to
L<moose-subscribe@perl.org>

=head1 DEPENDENCIES

This module requires these other modules and libraries: