llvm-project/libcxx/test/diagnostics/syserr/syserr.hash/error_code.pass.cpp

43 lines
923 B
C++

//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <functional>
// template <class T>
// struct hash
// : public unary_function<T, size_t>
// {
// size_t operator()(T val) const;
// };
// Not very portable
#include <system_error>
#include <cassert>
#include <type_traits>
void
test(int i)
{
typedef std::error_code T;
typedef std::hash<T> H;
static_assert((std::is_base_of<std::unary_function<T, std::size_t>,
H>::value), "");
H h;
T ec(i, std::system_category());
assert(h(ec) == i);
}
int main()
{
test(0);
test(2);
test(10);
}