nullable_string16.h 1.28 KB
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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.

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#ifndef BUTIL_STRINGS_NULLABLE_STRING16_H_
#define BUTIL_STRINGS_NULLABLE_STRING16_H_
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#include <iosfwd>

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#include "butil/base_export.h"
#include "butil/strings/string16.h"
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namespace butil {
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// 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) { }
  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);
}

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BUTIL_EXPORT std::ostream& operator<<(std::ostream& out,
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                                     const NullableString16& value);

}  // namespace

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#endif  // BUTIL_STRINGS_NULLABLE_STRING16_H_