front.pass.cpp
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//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
// <string_view>
// constexpr const _CharT& back();
#include <string_view>
#include <cassert>
#include "test_macros.h"
template <typename CharT>
bool test ( const CharT *s, size_t len ) {
typedef std::basic_string_view<CharT> SV;
SV sv ( s, len );
ASSERT_SAME_TYPE(decltype(sv.front()), typename SV::const_reference);
LIBCPP_ASSERT_NOEXCEPT( sv.front());
assert ( sv.length() == len );
assert ( sv.front() == s[0] );
return &sv.front() == s;
}
int main(int, char**) {
assert ( test ( "ABCDE", 5 ));
assert ( test ( "a", 1 ));
assert ( test ( L"ABCDE", 5 ));
assert ( test ( L"a", 1 ));
#if TEST_STD_VER >= 11
assert ( test ( u"ABCDE", 5 ));
assert ( test ( u"a", 1 ));
assert ( test ( U"ABCDE", 5 ));
assert ( test ( U"a", 1 ));
#endif
#if TEST_STD_VER >= 11
{
constexpr std::basic_string_view<char> sv ( "ABC", 2 );
static_assert ( sv.length() == 2, "" );
static_assert ( sv.front() == 'A', "" );
}
#endif
return 0;
}