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//===----------------------------------------------------------------------===//
//
// 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.
//
//===----------------------------------------------------------------------===//
// <array>
// reference operator[] (size_type)
// const_reference operator[] (size_type); // constexpr in C++14
// reference at (size_type)
// const_reference at (size_type); // constexpr in C++14
#include <array>
#include <cassert>
int main()
{
{
typedef double T;
typedef std::array<T, 3> C;
C c = {1, 2, 3.5};
C::reference r1 = c.at(0);
assert(r1 == 1);
r1 = 5.5;
assert(c.front() == 5.5);
C::reference r2 = c.at(2);
assert(r2 == 3.5);
r2 = 7.5;
assert(c.back() == 7.5);
try { (void) c.at(3); }
catch (const std::out_of_range &) {}
}
{
typedef double T;
typedef std::array<T, 3> C;
const C c = {1, 2, 3.5};
C::const_reference r1 = c.at(0);
assert(r1 == 1);
C::const_reference r2 = c.at(2);
assert(r2 == 3.5);
try { (void) c.at(3); }
catch (const std::out_of_range &) {}
}
#if _LIBCPP_STD_VER > 11
{
typedef double T;
typedef std::array<T, 3> C;
constexpr C c = {1, 2, 3.5};
constexpr T t1 = c.at(0);
static_assert (t1 == 1, "");
constexpr T t2 = c.at(2);
static_assert (t2 == 3.5, "");
}
#endif
}
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