Add gin, a lightweight bindings system for V8

gin/per_isolate_data.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_PER_ISOLATE_DATA_H_
+#define GIN_PER_ISOLATE_DATA_H_
+
+#include <map>
+
+#include "base/basictypes.h"
+#include "gin/wrapper_info.h"
+#include "v8/include/v8.h"
+
+namespace gin {
+
+class PerIsolateData {
+ public:
+  explicit PerIsolateData(v8::Isolate* isolate);
+  ~PerIsolateData();
+
+  static PerIsolateData* From(v8::Isolate* isolate);
+
+  void RegisterObjectTemplate(WrapperInfo* info,
+                              v8::Local<v8::ObjectTemplate> object_template);
+  v8::Handle<v8::Object> CreateObject(WrapperInfo* info);

[Aaron Boodman, 2013/11/09 21:40:35]

Seems a little odd to have CreateObject() here, rather than on the class that
creates the object template. If that is just to share the caching code, then you
could define something like:

template<typename T>
struct V8ClassConverter : public V8Converter<T> {
 ...
};

and have that guy have a private method that knows how to interact with
PerIsolateData, and which also calls a specialized CreateTemplate() method that
the templatized struct is expected to define.

[abarth-chromium, 2013/11/10 02:12:20]

For now, I think I'm just going to remove this function.  There aren't any
callers yet and we can figure out the best thing when we have the first caller. 
I thought for a while we could avoid allocating a new local handle when creating
the object, but we need to do that anyway, so you're right that we should
probably just have PerIsolateData vend a v8::Local<v8::ObjectTemplate> and call
NewInstance somewhere else.

+
+ private:
+  typedef std::map<
+      WrapperInfo*, v8::Eternal<v8::ObjectTemplate> > ObjectTemplateMap;
+
+  v8::Isolate* isolate_;
+  ObjectTemplateMap object_templates_;
+
+  DISALLOW_COPY_AND_ASSIGN(PerIsolateData);
+};
+
+}  // namespace gin
+
+#endif  // GIN_PER_ISOLATE_DATA_H_