src/model/model_base.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Copyright 2012 Jean Privat <jean@pryen.org>
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #     http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 # The abstract concept of model and related common things
  18 module model_base
  19
  20 # The container class of a Nit object-oriented model.
  21 # A model knows modules, classes and properties and can retrieve them.
  22 class Model
  23 end
  24
  25 # A named and possibly documented entity in the model.
  26 # This class is usefull to generalize presentation of entities to the human.
  27 abstract class MEntity
  28         # The short (unqualified) name of this model entity
  29         fun name: String is abstract
  30
  31         # A Model Entity has a direct link to its model
  32         fun model: Model is abstract
  33 end
  34
  35 # Something that represents a concern
  36 abstract class MConcern
  37         super MEntity
  38         # The concern that contains `self` or null if `self` is the root of the concern hierarchy
  39         fun parent_concern: nullable MConcern is abstract
  40 end
  41
  42 # A visibility (for modules, class and properties)
  43 # Valid visibility are:
  44 #
  45 #  * `intrude_visibility`
  46 #  * `public_visibility`
  47 #  * `protected_visibility`
  48 #  * `none_visibility`
  49 #
  50 # Note this class is basically an enum.
  51 # FIXME: use a real enum once user-defined enums are available
  52 class MVisibility
  53         super Comparable
  54         redef type OTHER: MVisibility
  55
  56         redef var to_s: String
  57
  58         private var level: Int
  59
  60         private init(s: String, level: Int)
  61         do
  62                 self.to_s = s
  63                 self.level = level
  64         end
  65
  66         # Is self give less visibility than other
  67         # none < private < protected < public < intrude
  68         redef fun <(other)
  69         do
  70                 return self.level < other.level
  71         end
  72 end
  73
  74 fun intrude_visibility: MVisibility do return once new MVisibility("intrude", 5)
  75 fun public_visibility: MVisibility do return once new MVisibility("public", 4)
  76 fun protected_visibility: MVisibility do return once new MVisibility("protected", 3)
  77 fun private_visibility: MVisibility do return once new MVisibility("private", 2)
  78 fun none_visibility: MVisibility do return once new MVisibility("none", 1)