tests/test_variance_param.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Copyright 2004-2008 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 class A
  18         type T: A
  19         type U: B
  20         fun foo(a: T) do a.out
  21         fun bar(b: U) do b.out
  22         fun baz(i: C) do i.out
  23         fun out do 'A'.output
  24
  25         init do end
  26 end
  27
  28 class B
  29         super A
  30         redef type T: B
  31         redef type U: C
  32         redef fun foo(a: T) do a.out
  33         redef fun bar(b: U) do b.out
  34         redef fun baz(i: C) do i.out
  35         redef fun out do 'B'.output
  36
  37         init do end
  38 end
  39
  40 class C
  41         super B
  42         redef type T: C
  43         redef fun foo(a: T) do a.out
  44         redef fun bar(b: U) do b.out
  45         redef fun output do i.output
  46         redef fun out
  47         do
  48                 var i: Object = self
  49                 if i isa C then
  50                         i.output
  51                 else
  52                         'X'.output
  53                 end
  54         end
  55         var i: Int
  56         init (i:Int) do self.i = i
  57 end
  58 var a = new A
  59 var b = new B
  60 var ab: A = b
  61 var i = new C(5)
  62 var ai: A = i
  63 var bi: B = i
  64
  65 a.foo(a)
  66 a.foo(b)
  67 a.foo(i)
  68 a.bar(b)
  69 a.bar(i)
  70 a.baz(i)
  71 #alt1#ab.foo(a) # covariant
  72 ab.foo(b)
  73 ab.foo(i)
  74 #alt2#ab.bar(b) # covariant
  75 ab.bar(i)
  76 ab.baz(i)
  77 #alt3#ai.foo(a) # covariant
  78 #alt4#ai.foo(b) # covariant
  79 ai.foo(i)
  80 #alt5#ai.bar(b) # covariant
  81 ai.bar(i)
  82 ai.baz(i)
  83
  84 b.foo(b)
  85 b.foo(i)
  86 b.bar(i)
  87 b.baz(i)
  88 #alt6#bi.foo(b) # covariant
  89 bi.foo(i)
  90 bi.bar(i)
  91 bi.baz(i)
  92
  93 i.foo(i)
  94 i.bar(i)
  95 i.baz(i)