Nobody is a gem to add shorthand ability of implementing the Null Object Pattern in a class.
$ gem install nobodyUsing nobody is easy, just include the module in your class and then use one if its methods, returns_nil_for, returns_true_for, or returns_false_for. You can specify any other methods normally in the class.
class NullOdysseus
include Nobody
returns_nil_for :name, :email_address
returns_true_for :is_adventurer?, :alive?
returns_false_for :dead?, :cyclops?
def hometown
'Itaca'
end
end
o = NullOdysseus.new
o.name #=> nil
o.alive? #=> true
o.dead? #=> falsePersonne est un gem pour utiliser facilement la Modèle d'objet Null dans un class.
$ gem install nobodyUtiliser personne est facile. On doit seulement inclure le module dans son class et puis utiliser un de ses méthodes, returns_nil_for, returns_true_for, ou returns_false_for. On peut écrire des autre méthodes comme d'habitude.
class NullOdysseus
include Nobody
returns_nil_for :name, :email_address
returns_true_for :is_adventurer?, :alive?
returns_false_for :dead?, :cyclops?
def hometown
'Itaca'
end
end
o = NullOdysseus.new
o.name #=> nil
o.alive? #=> true
o.dead? #=> falseThanks to Ben Orenstein (@r00k) for his talk at RMR12 on refactoring, which included this pattern.
Copyright (c) 2012 GordonDiggs
MIT License
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.