tests/base_safe2.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 redef class Int
  16         fun foo do print self
  17 end
  18
  19 class A
  20         var x: Int
  21 end
  22
  23 class B
  24         var a: nullable A = null
  25 end
  26
  27 class C
  28         var x: Int
  29         var c: nullable C = null
  30 end
  31
  32 class D
  33         var x: nullable Int
  34         var d: nullable D = null
  35 end
  36
  37 var b = new B
  38
  39 #alt1#b.a?.x.foo
  40
  41 var a = new A(10)
  42
  43 b.a = a
  44 print "b.a.x: {b.a?.x or else "nothing"}"
  45
  46 var c1 = new C(1)
  47 var c2 = new C(10)
  48 var c3 = new C(100)
  49 c1.c = c2
  50 c2.c = c3
  51
  52 print c1.c?.c?.x or else "null"
  53 print c1.c?.c?.c or else "null"
  54
  55 var d1 = new D(1)
  56 var d2 = new D(10)
  57 var d3 = new D(null)
  58
  59 d1.d = d2
  60 d2.d = d3
  61
  62 print d1.d?.x or else "null"
  63 print d1.d?.d?.x or else "null"