Function getConstructor

demo/js/index.js:2673–2676

(C)

  return same(a, b);
};
var getConstructor = function(C){
  var S = anObject(C)[SPECIES];
  return S != undefined ? S : C;
};
var isThenable = function(it){
  var then;
  return isObject(it) && typeof (then = it.then) == 'function' ? then : false;