gcc/testsuite/gdc.test/compilable/test19203.d

   1 //https://issues.dlang.org/show_bug.cgi?id=19203
   2 struct BoolWithErr {
   3     bool b;
   4     string error;
   5     alias b this;
   6 }
   7
   8 struct Foo {
   9     int popBack() { return 0; }
  10 }
  11
  12 struct Bar {}
  13
  14 template hasPopBack(T) {
  15     static if (!is(typeof(T.init.popBack)))
  16         enum hasPopBack = BoolWithErr(false, T.stringof~" does not have popBack");
  17     else
  18         enum hasPopBack = BoolWithErr(true,"");
  19 }
  20
  21 void test()
  22 {
  23     static assert( hasPopBack!Foo);
  24     static assert(!hasPopBack!Bar);
  25     static assert( hasPopBack!Foo && !hasPopBack!Bar);
  26 }
  27