56 lines
1.7 KiB
C
56 lines
1.7 KiB
C
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// Copyright (c) 2010 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef BASE_STRINGS_NULLABLE_STRING16_H_
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#define BASE_STRINGS_NULLABLE_STRING16_H_
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#include <iosfwd>
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#include "base/base_export.h"
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#include "base/optional.h"
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#include "base/strings/string16.h"
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#include "base/strings/string_util.h"
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namespace base {
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// This class is a simple wrapper for string16 which also contains a null
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// state. This should be used only where the difference between null and
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// empty is meaningful.
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class BASE_EXPORT NullableString16 {
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public:
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NullableString16();
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NullableString16(const NullableString16& other);
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NullableString16(NullableString16&& other);
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NullableString16(const string16& string, bool is_null);
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explicit NullableString16(Optional<string16> optional_string16);
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~NullableString16();
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NullableString16& operator=(const NullableString16& other);
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NullableString16& operator=(NullableString16&& other);
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const string16& string() const {
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return string_ ? *string_ : EmptyString16();
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}
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bool is_null() const { return !string_; }
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const Optional<string16>& as_optional_string16() const { return string_; }
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private:
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Optional<string16> string_;
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};
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inline bool operator==(const NullableString16& a, const NullableString16& b) {
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return a.as_optional_string16() == b.as_optional_string16();
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}
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inline bool operator!=(const NullableString16& a, const NullableString16& b) {
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return !(a == b);
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}
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BASE_EXPORT std::ostream& operator<<(std::ostream& out,
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const NullableString16& value);
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} // namespace base
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#endif // BASE_STRINGS_NULLABLE_STRING16_H_
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