//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14
// type_traits
// is_invocable
// Most testing of is_invocable is done within the [meta.trans.other] result_of
// tests.
// Fn and all types in the template parameter pack ArgTypes shall be
// complete types, cv void, or arrays of unknown bound.
#include <type_traits>
#include <functional>
#include <memory>
#include <vector>
#include "test_macros.h"
struct Tag {};
struct DerFromTag : Tag {};
struct Implicit {
Implicit(int) {}
};
struct Explicit {
explicit Explicit(int) {}
};
struct NotCallableWithInt {
int operator()(int) = delete;
int operator()(Tag) { return 42; }
};
struct Sink {
template <class ...Args>
void operator()(Args&&...) const {}
};
int main(int, char**) {
using AbominableFunc = void(...) const;
// Non-callable things
{
static_assert(!std::is_invocable<void>::value, "");
static_assert(!std::is_invocable<const void>::value, "");
static_assert(!std::is_invocable<volatile void>::value, "");
static_assert(!std::is_invocable<const volatile void>::value, "");
static_assert(!std::is_invocable<std::nullptr_t>::value, "");
static_assert(!std::is_invocable<int>::value, "");
static_assert(!std::is_invocable<double>::value, "");
static_assert(!std::is_invocable<int[]>::value, "");
static_assert(!std::is_invocable<int[3]>::value, "");
static_assert(!std::is_invocable<int*>::value, "");
static_assert(!std::is_invocable<const int*>::value, "");
static_assert(!std::is_invocable<int const*>::value, "");
static_assert(!std::is_invocable<int&>::value, "");
static_assert(!std::is_invocable<const int&>::value, "");
static_assert(!std::is_invocable<int&&>::value, "");
static_assert(!std::is_invocable<std::vector<int> >::value, "");
static_assert(!std::is_invocable<std::vector<int*> >::value, "");
static_assert(!std::is_invocable<std::vector<int**> >::value, "");
static_assert(!std::is_invocable<AbominableFunc>::value, "");
// with parameters
static_assert(!std::is_invocable<int, int>::value, "");
static_assert(!std::is_invocable<int, double, float>::value, "");
static_assert(!std::is_invocable<int, char, float, double>::value, "");
static_assert(!std::is_invocable<Sink, AbominableFunc>::value, "");
static_assert(!std::is_invocable<Sink, void>::value, "");
static_assert(!std::is_invocable<Sink, const volatile void>::value,
"");
static_assert(!std::is_invocable_r<int, void>::value, "");
static_assert(!std::is_invocable_r<int, const void>::value, "");
static_assert(!std::is_invocable_r<int, volatile void>::value, "");
static_assert(!std::is_invocable_r<int, const volatile void>::value, "");
static_assert(!std::is_invocable_r<int, std::nullptr_t>::value, "");
static_assert(!std::is_invocable_r<int, int>::value, "");
static_assert(!std::is_invocable_r<int, double>::value, "");
static_assert(!std::is_invocable_r<int, int[]>::value, "");
static_assert(!std::is_invocable_r<int, int[3]>::value, "");
static_assert(!std::is_invocable_r<int, int*>::value, "");
static_assert(!std::is_invocable_r<int, const int*>::value, "");
static_assert(!std::is_invocable_r<int, int const*>::value, "");
static_assert(!std::is_invocable_r<int, int&>::value, "");
static_assert(!std::is_invocable_r<int, const int&>::value, "");
static_assert(!std::is_invocable_r<int, int&&>::value, "");
static_assert(!std::is_invocable_r<int, std::vector<int> >::value, "");
static_assert(!std::is_invocable_r<int, std::vector<int*> >::value, "");
static_assert(!std::is_invocable_r<int, std::vector<int**> >::value, "");
static_assert(!std::is_invocable_r<void, AbominableFunc>::value, "");
// with parameters
static_assert(!std::is_invocable_r<int, int, int>::value, "");
static_assert(!std::is_invocable_r<int, int, double, float>::value, "");
static_assert(!std::is_invocable_r<int, int, char, float, double>::value,
"");
static_assert(!std::is_invocable_r<void, Sink, AbominableFunc>::value, "");
static_assert(!std::is_invocable_r<void, Sink, void>::value, "");
static_assert(!std::is_invocable_r<void, Sink, const volatile void>::value,
"");
}
{
using Fn = int (Tag::*)(int);
using RFn = int (Tag::*)(int)&&;
// INVOKE bullet 1, 2 and 3
{
// Bullet 1
static_assert(std::is_invocable<Fn, Tag&, int>::value, "");
static_assert(std::is_invocable<Fn, DerFromTag&, int>::value, "");
static_assert(std::is_invocable<RFn, Tag&&, int>::value, "");
static_assert(!std::is_invocable<RFn, Tag&, int>::value, "");
static_assert(!std::is_invocable<Fn, Tag&>::value, "");
static_assert(!std::is_invocable<Fn, Tag const&, int>::value, "");
}
{
// Bullet 2
using T = std::reference_wrapper<Tag>;
using DT = std::reference_wrapper<DerFromTag>;
using CT = std::reference_wrapper<const Tag>;
static_assert(std::is_invocable<Fn, T&, int>::value, "");
static_assert(std::is_invocable<Fn, DT&, int>::value, "");
static_assert(std::is_invocable<Fn, const T&, int>::value, "");
static_assert(std::is_invocable<Fn, T&&, int>::value, "");
static_assert(!std::is_invocable<Fn, CT&, int>::value, "");
static_assert(!std::is_invocable<RFn, T, int>::value, "");
}
{
// Bullet 3
using T = Tag*;
using DT = DerFromTag*;
using CT = const Tag*;
using ST = std::unique_ptr<Tag>;
static_assert(std::is_invocable<Fn, T&, int>::value, "");
static_assert(std::is_invocable<Fn, DT&, int>::value, "");
static_assert(std::is_invocable<Fn, const T&, int>::value, "");
static_assert(std::is_invocable<Fn, T&&, int>::value, "");
static_assert(std::is_invocable<Fn, ST, int>::value, "");
static_assert(!std::is_invocable<Fn, CT&, int>::value, "");
static_assert(!std::is_invocable<RFn, T, int>::value, "");
}
}
{
// Bullets 4, 5 and 6
using Fn = int(Tag::*);
static_assert(!std::is_invocable<Fn>::value, "");
{
// Bullet 4
static_assert(std::is_invocable<Fn, Tag&>::value, "");
static_assert(std::is_invocable<Fn, DerFromTag&>::value, "");
static_assert(std::is_invocable<Fn, Tag&&>::value, "");
static_assert(std::is_invocable<Fn, Tag const&>::value, "");
}
{
// Bullet 5
using T = std::reference_wrapper<Tag>;
using DT = std::reference_wrapper<DerFromTag>;
using CT = std::reference_wrapper<const Tag>;
static_assert(std::is_invocable<Fn, T&>::value, "");
static_assert(std::is_invocable<Fn, DT&>::value, "");
static_assert(std::is_invocable<Fn, const T&>::value, "");
static_assert(std::is_invocable<Fn, T&&>::value, "");
static_assert(std::is_invocable<Fn, CT&>::value, "");
}
{
// Bullet 6
using T = Tag*;
using DT = DerFromTag*;
using CT = const Tag*;
using ST = std::unique_ptr<Tag>;
static_assert(std::is_invocable<Fn, T&>::value, "");
static_assert(std::is_invocable<Fn, DT&>::value, "");
static_assert(std::is_invocable<Fn, const T&>::value, "");
static_assert(std::is_invocable<Fn, T&&>::value, "");
static_assert(std::is_invocable<Fn, ST>::value, "");
static_assert(std::is_invocable<Fn, CT&>::value, "");
}
}
{ // INVOKE bullet 7
{// Function pointer
using Fp = void(*)(Tag&, int);
static_assert(std::is_invocable<Fp, Tag&, int>::value, "");
static_assert(std::is_invocable<Fp, DerFromTag&, int>::value, "");
static_assert(!std::is_invocable<Fp, const Tag&, int>::value, "");
static_assert(!std::is_invocable<Fp>::value, "");
static_assert(!std::is_invocable<Fp, Tag&>::value, "");
}
{
// Function reference
using Fp = void (&)(Tag&, int);
static_assert(std::is_invocable<Fp, Tag&, int>::value, "");
static_assert(std::is_invocable<Fp, DerFromTag&, int>::value, "");
static_assert(!std::is_invocable<Fp, const Tag&, int>::value, "");
static_assert(!std::is_invocable<Fp>::value, "");
static_assert(!std::is_invocable<Fp, Tag&>::value, "");
}
{
// Function object
using Fn = NotCallableWithInt;
static_assert(std::is_invocable<Fn, Tag>::value, "");
static_assert(!std::is_invocable<Fn, int>::value, "");
}
}
{
// Check that the conversion to the return type is properly checked
using Fn = int (*)();
static_assert(std::is_invocable_r<Implicit, Fn>::value, "");
static_assert(std::is_invocable_r<double, Fn>::value, "");
static_assert(std::is_invocable_r<const volatile void, Fn>::value, "");
static_assert(!std::is_invocable_r<Explicit, Fn>::value, "");
}
{
// Check for is_invocable_v
using Fn = void (*)();
static_assert(std::is_invocable_v<Fn>, "");
static_assert(!std::is_invocable_v<Fn, int>, "");
}
{
// Check for is_invocable_r_v
using Fn = void (*)();
static_assert(std::is_invocable_r_v<void, Fn>, "");
static_assert(!std::is_invocable_r_v<int, Fn>, "");
}
return 0;
}