Aliases

A factory can register one or more aliases — alternative names that look up the same definition. Aliases also drive the implicit-association lookup (see Associations), so a :post factory whose :author column references a :user factory is one alias away from working without an explicit declaration.

Declaring aliases

Pass an :aliases named argument when defining a factory. It accepts either a single string or a list:

define {
  .factory: 'user', :aliases<author commenter>, {
    .fname: 'Greg';
  };
};

ORM::Factory.factory-by-name('author').name;     # 'user'
ORM::Factory.factory-by-name('commenter').name;  # 'user'
ORM::Factory.aliases<author>;                    # 'user'

factory-by-name returns the same FactoryDefinition for the canonical name and every alias, so any downstream code that looks up the factory sees the same record.

Collision detection

Aliases share a namespace with factory names. Any collision raises X::ORM::Factory::DuplicateAlias immediately:

# alias would shadow an existing factory
define {
  .factory: 'user',  { ; };
  .factory: 'other', :aliases<user>, { ; };   # raises
};

# two factories cannot claim the same alias
define {
  .factory: 'user',  :aliases<author>, { ; };
  .factory: 'other', :aliases<author>, { ; }; # raises
};

# a new factory cannot reuse an existing alias
define {
  .factory: 'user', :aliases<author>, { ; };
};
define {
  .factory: 'author', { ; };   # raises
};

Reload

ORM::Factory.reload clears the alias map along with the registry. Looking up an alias after a reload raises X::ORM::Factory::UnknownFactory.