frame_id (Debugger::Context)

    /*
     *   call-seq:
     *      context.frame_method(frame_position=0) -> sym
     *
     *   Returns the sym of the called method.
     */
    static VALUE
    context_frame_id(int argc, VALUE *argv, VALUE self)
    {
        VALUE frame;
        debug_context_t *debug_context;
        ID id;

        debug_check_started();
        frame = optional_frame_position(argc, argv);
        Data_Get_Struct(self, debug_context_t, debug_context);

        id = GET_FRAME->id;
        return id ? ID2SYM(id): Qnil;
    }