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// 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/optional.h"
#include "base/strings/string16.h"
#include "base/strings/string_util.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 BASE_EXPORT NullableString16 {
public:
NullableString16();
NullableString16(const NullableString16& other);
NullableString16(NullableString16&& other);
NullableString16(const string16& string, bool is_null);
explicit NullableString16(Optional<string16> optional_string16);
~NullableString16();
NullableString16& operator=(const NullableString16& other);
NullableString16& operator=(NullableString16&& other);
const string16& string() const {
return string_ ? *string_ : EmptyString16();
}
bool is_null() const { return !string_; }
const Optional<string16>& as_optional_string16() const { return string_; }
private:
Optional<string16> string_;
};
inline bool operator==(const NullableString16& a, const NullableString16& b) {
return a.as_optional_string16() == b.as_optional_string16();
}
inline bool operator!=(const NullableString16& a, const NullableString16& b) {
return !(a == b);
}
BASE_EXPORT std::ostream& operator<<(std::ostream& out,
const NullableString16& value);
} // namespace base
#endif // BASE_STRINGS_NULLABLE_STRING16_H_
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