Implement string suffixes from N3642

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@186956 91177308-0d34-0410-b5e6-96231b3b80d8

include/string

@@ -422,6 +422,11 @@ template <> struct hash<u16string>;
 template <> struct hash<u32string>;
 template <> struct hash<wstring>;
 
+basic_string<char>     operator "" s( const char *str,     size_t len ); // C++14
+basic_string<wchar_t>  operator "" s( const wchar_t *str,  size_t len ); // C++14
+basic_string<char16_t> operator "" s( const char16_t *str, size_t len ); // C++14
+basic_string<char32_t> operator "" s( const char32_t *str, size_t len ); // C++14
+
 }  // std
 
 */
@@ -4097,6 +4102,42 @@ getline(basic_istream<_CharT, _Traits>&& __is,
 
 #endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
+#if _LIBCPP_STD_VER > 11 
+// Literal suffixes for basic_string [basic.string.literals]
+// inline // Deviation from N3690.
+//    We believe the inline to be a defect and have submitted an LWG issue.
+//    An LWG issue number has not yet been assigned.
+namespace literals
+{
+  inline namespace string_literals
+  {
+	inline _LIBCPP_INLINE_VISIBILITY
+	basic_string<char> operator "" s( const char *__str, size_t __len )
+	{
+		return basic_string<char> (__str, __len);
+	}
+
+	inline _LIBCPP_INLINE_VISIBILITY
+	basic_string<wchar_t> operator "" s( const wchar_t *__str, size_t __len )
+	{
+		return basic_string<wchar_t> (__str, __len);
+	}
+
+	inline _LIBCPP_INLINE_VISIBILITY
+	basic_string<char16_t> operator "" s( const char16_t *__str, size_t __len )
+	{
+		return basic_string<char16_t> (__str, __len);
+	}
+
+	inline _LIBCPP_INLINE_VISIBILITY
+	basic_string<char32_t> operator "" s( const char32_t *__str, size_t __len )
+	{
+		return basic_string<char32_t> (__str, __len);
+	}
+  }
+}
+#endif
+
 _LIBCPP_EXTERN_TEMPLATE(class basic_string<char>)
 _LIBCPP_EXTERN_TEMPLATE(class basic_string<wchar_t>)
 

test/strings/basic.string.literals/literal.pass.cpp

@@ -0,0 +1,47 @@
+// -*- 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.
+//
+//===----------------------------------------------------------------------===//
+#include <string>
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11 
+    using namespace std::literals::string_literals;
+
+	static_assert ( std::is_same<decltype(   "Hi"s), std::string>::value, "" );
+	static_assert ( std::is_same<decltype( u8"Hi"s), std::string>::value, "" );
+	static_assert ( std::is_same<decltype(  L"Hi"s), std::wstring>::value, "" );
+	static_assert ( std::is_same<decltype(  u"Hi"s), std::u16string>::value, "" );
+	static_assert ( std::is_same<decltype(  U"Hi"s), std::u32string>::value, "" );
+	
+	std::string foo;
+	std::wstring Lfoo;
+	std::u16string ufoo;
+	std::u32string Ufoo;
+	
+	foo  =   ""s; 	assert( foo.size() == 0);
+	foo  = u8""s; 	assert( foo.size() == 0);
+	Lfoo =  L""s; 	assert(Lfoo.size() == 0);
+	ufoo =  u""s; 	assert(ufoo.size() == 0);
+	Ufoo =  U""s; 	assert(Ufoo.size() == 0);
+	
+	foo  =   " "s; 	assert( foo.size() == 1);
+	foo  = u8" "s; 	assert( foo.size() == 1);
+	Lfoo =  L" "s; 	assert(Lfoo.size() == 1);
+	ufoo =  u" "s; 	assert(ufoo.size() == 1);
+	Ufoo =  U" "s; 	assert(Ufoo.size() == 1);
+	
+	foo  =   "ABC"s; 	assert( foo ==   "ABC");   assert( foo == std::string   (  "ABC"));
+	foo  = u8"ABC"s; 	assert( foo == u8"ABC");   assert( foo == std::string   (u8"ABC"));
+	Lfoo =  L"ABC"s; 	assert(Lfoo ==  L"ABC");   assert(Lfoo == std::wstring  ( L"ABC"));
+	ufoo =  u"ABC"s; 	assert(ufoo ==  u"ABC");   assert(ufoo == std::u16string( u"ABC"));
+	Ufoo =  U"ABC"s; 	assert(Ufoo ==  U"ABC");   assert(Ufoo == std::u32string( U"ABC"));
+#endif
+}

test/strings/basic.string.literals/literal1.fail.cpp

@@ -0,0 +1,22 @@
+// -*- 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.
+//
+//===----------------------------------------------------------------------===//
+#include <string>
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11 
+    using namespace std;
+
+	std::string foo  =   ""s;  // should fail w/conversion operator not found
+#else
+#error
+#endif
+}

test/strings/basic.string.literals/literal1.pass.cpp

@@ -0,0 +1,20 @@
+// -*- 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.
+//
+//===----------------------------------------------------------------------===//
+#include <string>
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11 
+    using namespace std::literals;
+
+	std::string foo  =   ""s;
+#endif
+}

test/strings/basic.string.literals/literal2.fail.cpp

@@ -0,0 +1,20 @@
+// -*- 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.
+//
+//===----------------------------------------------------------------------===//
+#include <string>
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11 
+	std::string foo  =   ""s;  // should fail w/conversion operator not found
+#else
+#error
+#endif
+}

test/strings/basic.string.literals/literal2.pass.cpp

@@ -0,0 +1,20 @@
+// -*- 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.
+//
+//===----------------------------------------------------------------------===//
+#include <string>
+#include <cassert>
+
+int main()
+{
+#if _LIBCPP_STD_VER > 11 
+    using namespace std::literals::string_literals;
+
+	std::string foo  =   ""s;
+#endif
+}