tests/base_is_optional.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #     http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14
  15 import core::kernel
  16
  17 fun foo(i: Int): Int
  18 do
  19         'f'.output
  20         i.output
  21         return i
  22 end
  23
  24 class A
  25         # needed on the new
  26         var i: Int
  27
  28         # initialized by the allocation
  29         var j: Int = foo(2)
  30
  31         # optional in the new, default value evaluated if `null` is given
  32         var k: Int = foo(3) is optional
  33
  34         # the `init` will initialize it
  35         var l: Int is noautoinit
  36         init do l = foo(4)
  37
  38         # initialized if needed on the first `read`
  39         var m: Int = foo(5) is lazy
  40
  41         fun set
  42         do
  43                 i = 10
  44                 j = 20
  45                 k = 30
  46                 l = 40
  47                 m = 50
  48         end
  49
  50         fun test
  51         do
  52                 #alt1#set
  53                 i.output
  54                 j.output
  55                 k.output
  56                 l.output
  57                 m.output
  58                 '\n'.output
  59         end
  60 end
  61
  62 var a
  63 a = new A(foo(100))
  64 a.test
  65 a = new A(foo(100), null)
  66 a.test
  67 a = new A(foo(100), foo(300))
  68 a.test