Mercurial > hg > CbC > CbC_gcc
view gcc/testsuite/g++.dg/cpp0x/variadic-mem_fn.C @ 131:84e7813d76e9
gcc-8.2
author | mir3636 |
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date | Thu, 25 Oct 2018 07:37:49 +0900 |
parents | 04ced10e8804 |
children |
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// { dg-do run { target c++11 } } // A basic implementation of TR1's mem_fn using variadic teplates // Contributed by Douglas Gregor <doug.gregor@gmail.com> #include <cassert> template<typename R, typename Class, typename... Args> class Mem_fn { public: explicit Mem_fn(R (Class::*pmf)(Args...)) : pmf(pmf) { } R operator()(Class& object, Args... args) { return (object.*pmf)(args...); } R operator()(Class* object, Args... args) { return (object->*pmf)(args...); } R (Class::*pmf)(Args...); }; template<typename R, typename Class, typename... Args> inline Mem_fn<R, Class, Args...> mem_fn(R (Class::* pmf)(Args...)) { return Mem_fn<R, Class, Args...>(pmf); } class X { public: int negate(int x) { return -x; } int plus(int x, int y) { return x + y; } }; int main() { X x; X* xp = &x; assert(mem_fn(&X::negate)(x, 17) == -17); assert(mem_fn(&X::negate)(xp, 17) == -17); assert(mem_fn(&X::plus)(x, 17, 25) == 42); assert(mem_fn(&X::plus)(xp, 17, 25) == 42); return 0; }