Begin implementing V8 bindings for Mojo

gin/arguments.h

+// Copyright 2013 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 GIN_ARGUMENTS_H_
+#define GIN_ARGUMENTS_H_
+
+#include "base/basictypes.h"
+#include "gin/converter.h"
+
+namespace gin {
+
+class Arguments {
+ public:
+  explicit Arguments(const v8::FunctionCallbackInfo<v8::Value>& info);
+  ~Arguments();
+
+  template<typename T>
+  bool Holder(T* out) {
+    return ConvertFromV8(info_.Holder(), out);
+  }
+
+  template<typename T>
+  bool GetNext(T* out) {
+    if (next_ >= info_.Length()) {
+      insufficient_arguments_ = true;
+      return false;
+    }
+    v8::Handle<v8::Value> val = info_[next_++];
+    return ConvertFromV8(val, out);
+  }
+
+  template<typename T>
+  void Return(T val) {
+    info_.GetReturnValue().Set(ConvertToV8(isolate_, val));
+  }
+
+  void ThrowError();
+  void ThrowTypeError(const std::string& message);
+
+  v8::Isolate* isolate() const { return isolate_; }
+
+ private:
+  v8::Isolate* isolate_;
+  const v8::FunctionCallbackInfo<v8::Value>& info_;
+  int next_;
+  bool insufficient_arguments_;
+
+  DISALLOW_COPY_AND_ASSIGN(Arguments);
+};
+
+}  // namespace gin
+
+#endif  // GIN_ARGUMENTS_H_