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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.
//
//===----------------------------------------------------------------------===//
// NOTE: Older versions of clang have a bug where they fail to evaluate
// string_view::at as a constant expression.
// XFAIL: clang-3.4, clang-3.3
// <string_view>
// constexpr const _CharT& at(size_type _pos) const;
#include <string_view>
#include <stdexcept>
#include <cassert>
#include "test_macros.h"
template <typename CharT>
void test ( const CharT *s, size_t len ) {
std::basic_string_view<CharT> sv ( s, len );
assert ( sv.length() == len );
for ( size_t i = 0; i < len; ++i ) {
assert ( sv.at(i) == s[i] );
assert ( &sv.at(i) == s + i );
}
#ifndef TEST_HAS_NO_EXCEPTIONS
try { sv.at(len); } catch ( const std::out_of_range & ) { return ; }
assert ( false );
#endif
}
int main () {
test ( "ABCDE", 5 );
test ( "a", 1 );
test ( L"ABCDE", 5 );
test ( L"a", 1 );
#if TEST_STD_VER >= 11
test ( u"ABCDE", 5 );
test ( u"a", 1 );
test ( U"ABCDE", 5 );
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.at(0) == 'A', "" );
static_assert ( sv.at(1) == 'B', "" );
}
#endif
}
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