//===----------------------------------------------------------------------===//
//
// 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.
//
//===----------------------------------------------------------------------===//
// <string_view>
// constexpr const_iterator begin() const;
#include <experimental/string_view>
#include <cassert>
template <class S>
void
test(S s)
{
const S& cs = s;
typename S::iterator b = s.begin();
typename S::const_iterator cb1 = cs.begin();
typename S::const_iterator cb2 = s.cbegin();
if (!s.empty())
{
assert( *b == s[0]);
assert( &*b == &s[0]);
assert( *cb1 == s[0]);
assert(&*cb1 == &s[0]);
assert( *cb2 == s[0]);
assert(&*cb2 == &s[0]);
}
assert( b == cb1);
assert( b == cb2);
assert(cb1 == cb2);
}
int main()
{
typedef std::experimental::string_view string_view;
typedef std::experimental::u16string_view u16string_view;
typedef std::experimental::u32string_view u32string_view;
typedef std::experimental::wstring_view wstring_view;
test(string_view ());
test(u16string_view());
test(u32string_view());
test(wstring_view ());
test(string_view ( "123"));
test(wstring_view (L"123"));
#if __cplusplus >= 201103L
test(u16string_view{u"123"});
test(u32string_view{U"123"});
#endif
#if _LIBCPP_STD_VER > 11
{
constexpr string_view sv { "123", 3 };
constexpr u16string_view u16sv {u"123", 3 };
constexpr u32string_view u32sv {U"123", 3 };
constexpr wstring_view wsv {L"123", 3 };
static_assert ( *sv.begin() == sv[0], "" );
static_assert ( *u16sv.begin() == u16sv[0], "" );
static_assert ( *u32sv.begin() == u32sv[0], "" );
static_assert ( *wsv.begin() == wsv[0], "" );
static_assert ( *sv.cbegin() == sv[0], "" );
static_assert ( *u16sv.cbegin() == u16sv[0], "" );
static_assert ( *u32sv.cbegin() == u32sv[0], "" );
static_assert ( *wsv.cbegin() == wsv[0], "" );
}
#endif
}