| // Copyright (c) 2010 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef BASE_STRINGS_NULLABLE_STRING16_H_ |
| #define BASE_STRINGS_NULLABLE_STRING16_H_ |
| |
| #include <iosfwd> |
| |
| #include "base/base_export.h" |
| #include "base/strings/string16.h" |
| |
| namespace base { |
| |
| // This class is a simple wrapper for string16 which also contains a null |
| // state. This should be used only where the difference between null and |
| // empty is meaningful. |
| class NullableString16 { |
| public: |
| NullableString16() : is_null_(true) { } |
| explicit NullableString16(bool is_null) : is_null_(is_null) { } |
| NullableString16(const string16& string, bool is_null) |
| : string_(string), is_null_(is_null) { |
| } |
| |
| const string16& string() const { return string_; } |
| bool is_null() const { return is_null_; } |
| |
| private: |
| string16 string_; |
| bool is_null_; |
| }; |
| |
| inline bool operator==(const NullableString16& a, const NullableString16& b) { |
| return a.is_null() == b.is_null() && a.string() == b.string(); |
| } |
| |
| inline bool operator!=(const NullableString16& a, const NullableString16& b) { |
| return !(a == b); |
| } |
| |
| BASE_EXPORT std::ostream& operator<<(std::ostream& out, |
| const NullableString16& value); |
| |
| } // namespace |
| |
| // TODO(avi) update users of NullableString16 to use the namespace and remove |
| // this "using". |
| using base::NullableString16; |
| |
| #endif // BASE_STRINGS_NULLABLE_STRING16_H_ |