fn_alias.cc


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#if 0
set -xe
trap 'rm -f a.out' EXIT
g++     -std=c++17 fn_alias.cc && ./a.out
clang++ -std=c++17 fn_alias.cc && ./a.out
exit 0
#endif

#include <cassert>
#include <cstdio>

// Function alias.

void say() {
  std::puts("say");
}

inline constexpr auto say_alias = say;

// Template function alias.
//
// One drawback is that template type deducation does not work through the
// function pointer. One would need to write some macro wrapper.

template <typename T, typename U>
auto add(T t, U u) -> decltype(t + u) {
  return t + u;
}

template <typename U>
inline constexpr auto add_int = add<int, U>;

// Test me.

int main() {
  say();
  say_alias();

  assert(add(2, 3) == add_int<int>(3, 2));
}