tests/base_attr_lazy3.nit

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   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 kernel
  16
  17 class A
  18         var prev: nullable A
  19         var value: Int is lazy do
  20                 if prev == null then return 0
  21                 var v = prev.value + 1
  22                 v.output
  23                 return v
  24         end
  25 end
  26
  27 var a0 = new A(null)
  28 var a1 = new A(a0)
  29 var a2 = new A(a1)
  30 var a3 = new A(a2)
  31
  32 '\n'.output
  33 a2.value.output
  34 '\n'.output
  35 a1.value.output
  36 '\n'.output
  37 a3.value.output