text: #include <mruby.h>
  #include <mruby/proc.h>
  #include <mruby/class.h>
  
  static mrb_value
  return_func_name(mrb_state *mrb, mrb_value self)
  {
    return mrb_cfunc_env_get(mrb, 0);
  }
  
  static mrb_value
  proc_new_cfunc_with_env(mrb_state *mrb, mrb_value self)
  {
    mrb_sym n;
    mrb_value n_val;
    mrb_method_t m;
    struct RProc *p;
    mrb_get_args(mrb, "n", &n);
    n_val = mrb_symbol_value(n);
    p = mrb_proc_new_cfunc_with_env(mrb, return_func_name, 1, &n_val);
    MRB_METHOD_FROM_PROC(m, p);
    mrb_define_method_raw(mrb, mrb_class_ptr(self), n, m);
    return self;
  }
  
  static mrb_value
  return_env(mrb_state *mrb, mrb_value self)
  {
    mrb_int idx;
    mrb_get_args(mrb, "i", &idx);
    return mrb_cfunc_env_get(mrb, idx);
  }
  
  static mrb_value
  cfunc_env_get(mrb_state *mrb, mrb_value self)
  {
    mrb_sym n;
    mrb_value *argv; mrb_int argc;
    mrb_method_t m;
    struct RProc *p;
    mrb_get_args(mrb, "na", &n, &argv, &argc);
    p = mrb_proc_new_cfunc_with_env(mrb, return_env, argc, argv);
    MRB_METHOD_FROM_PROC(m, p);
    mrb_define_method_raw(mrb, mrb_class_ptr(self), n, m);
    return self;
  }
  
  static mrb_value
  cfunc_without_env(mrb_state *mrb, mrb_value self)
  {
    return mrb_cfunc_env_get(mrb, 0);
  }
  
  void mrb_mruby_proc_ext_gem_test(mrb_state *mrb)
  {
    struct RClass *cls;
  
    cls = mrb_define_class(mrb, "ProcExtTest", mrb->object_class);
    mrb_define_module_function(mrb, cls, "mrb_proc_new_cfunc_with_env", proc_new_cfunc_with_env, MRB_ARGS_REQ(1));
    mrb_define_module_function(mrb, cls, "mrb_cfunc_env_get", cfunc_env_get, MRB_ARGS_REQ(2));
    mrb_define_module_function(mrb, cls, "cfunc_without_env", cfunc_without_env, MRB_ARGS_NONE());
  }
  