third_party/blink/renderer/platform/bindings/shared_persistent.h

/*
 * Copyright (C) 2009 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 * this software without specific prior written permission.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_BINDINGS_SHARED_PERSISTENT_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_BINDINGS_SHARED_PERSISTENT_H_

#include "base/memory/scoped_refptr.h"
#include "third_party/blink/renderer/platform/bindings/scoped_persistent.h"
#include "third_party/blink/renderer/platform/wtf/ref_counted.h"
#include "v8/include/v8.h"

namespace blink {

// A ref counted version of ScopedPersistent. This class is intended for use by
// ScriptValue and not for normal use. Consider using ScopedPersistent directly
// instead.
template <typename T>
class SharedPersistent : public RefCounted<SharedPersistent<T>> {
 public:
  static scoped_refptr<SharedPersistent<T>> Create(v8::Local<T> value,
                                                   v8::Isolate* isolate) {
    return base::AdoptRef(new SharedPersistent<T>(value, isolate));
  }

  v8::Local<T> NewLocal(v8::Isolate* isolate) const {
    return value_.NewLocal(isolate);
  }

  bool IsEmpty() { return value_.IsEmpty(); }

  bool operator==(const SharedPersistent<T>& other) {
    return value_ == other.value_;
  }

 private:
  explicit SharedPersistent(v8::Local<T> value, v8::Isolate* isolate)
      : value_(isolate, value) {}
  ScopedPersistent<T> value_;

  DISALLOW_COPY_AND_ASSIGN(SharedPersistent);
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_BINDINGS_SHARED_PERSISTENT_H_