Abstracting Data Types about api

[cjihrig]

This seems logical. Could you go into more detail about:

There are alternative solutions (including the one we use with jxcore native interface).

[trevnorris]

If you'd like, make the file native/data_types.md and write out how you think this should be implemented. Then throw it up in a PR.

For now we'll be pretty loose with merging stuff in. Then once there are more opinions, discussions can be had about the existing docs and what changes should be made.

[trevnorris]

Or if you'd like just throw it in a gist and I'll land it for you.

[obastemur]

@cjihrig @trevnorris Okay. I'm working on it.

[mhdawson]

Looking at the initial types in https://github.com/nodejs/api/blob/master/native/data_types.md and in particular:

struct JSValue {
  void* env_;
  void* data_;
  uintptr_t flags_;
};

We may find that we need to bundle the env_ into more than just the JSValue and possibly extend beyond a single pointer, so pulling out its definition into its own struct might make sense.

I also think making the structures opaque, and limiting access through helper methods would leave as more flexibility to change under the covers.

[trevnorris]

pulling out its definition into its own struct might make sense.

Have an idea what would go into that struct, or should there simply be a placeholder?

[mhdawson]

I think for now it would just be void* _env.

As to what might go there later some things that come to mind
1) the original description of _env sounds like it would point to java script engine (ex v8) structures. We might also need something at the Node or libuv level
2) It might be the place to add function pointers for the API (less sure on this front)

[obastemur]

1. the original description of _env sounds like it would point to java script engine (ex v8) structures. We might also need something at the Node or libuv level

@mhdawson Why JSValue is related to other parts of the Node?

[mhdawson]

@obastemur I think this work is going to be pulled into the work that @stefanmb and @ianwjhalliday are pushing forward. Do you think we still need this issue.