638040 - Operation callback functions should take a closure pointer

Status: NEW

(Core :: JavaScript Engine, defect)

Description

[Jim Blandy :jimb]

When setting an operation callback, it should be possible to provide a pointer to be passed through to the function, so that operation callback functions wouldn't necessarily need to rely on global variables or JSContext-specific data to do their job.

If we wanted to be typesafe in high C++ fashion, we could replace the operation callback function with an instance of a class derived from something like:

class OperationCallback {
  virtual Invoke(JSContext *cx);
};

Then the 'this' argument would do the job of the proposed closure argument.