javascript - Deep Freeze any type -


is enough deep freeze kind of type?

function freeze(obj) {   if (typeof obj === 'object') {     reflect.ownkeys(obj).foreach((key) => {freeze(obj[key])});   }    return object.freeze(obj); }

no. unfortunately, javascript still doesn't have way that. example, date instances cannot frozen:

var dt = new date(2016, 11, 27);  console.log(dt.getdate()); // 27  object.freeze(dt);  dt.setdate(dt.getdate() + 1);  console.log(dt.getdate()); // 28

some other issues/notes:

  • as matías said, functions objects, typeof give "function" them.
  • reflect.ownkeys gives object's own keys, not keys prototypes. depending on definition of "deep freeze," may need copy inherited properties object before freezing it.

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