libcxx/test/std/utilities/function.objects/func.memfn/member_data.compile.fail.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9
  10 // <functional>
  11
  12 // template<Returnable R, class T> unspecified mem_fn(R T::* pm);
  13
  14 #include <functional>
  15 #include <cassert>
  16
  17 struct A
  18 {
  19     double data_;
  20 };
  21
  22 template <class F>
  23 void
  24 test(F f)
  25 {
  26     {
  27     A a;
  28     f(a) = 5;
  29     assert(a.data_ == 5);
  30     A* ap = &a;
  31     f(ap) = 6;
  32     assert(a.data_ == 6);
  33     const A* cap = ap;
  34     assert(f(cap) == f(ap));
  35     f(cap) = 7;
  36     }
  37 }
  38
  39 int main(int, char**)
  40 {
  41     test(std::mem_fn(&A::data_));
  42
  43   return 0;
  44 }