const result = Object.values(obj).map(heavyComputation);
      cache.set(obj, result);
      return result;
    }
    

This only works if your function's input is an object. Moreover, even if the
input is never passed in again, the result still remains forever in the cache.
A more effective way is to use a [ ` Map ` ](/en-
US/docs/Web/JavaScript/Reference/Global_Objects/Map) paired with [ ` WeakRef `
](/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakRef) objects, which
allows you to associate any type of input value with its respective
(potentially large) computation result. See the [ WeakRefs and
FinalizationRegistry ](/en-
US/docs/Web/JavaScript/Memory_management#weakrefs_and_finalizationregistry)
example for more details.

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-weakmap-objects  ](https://tc39.es/ecma262/multipage/keyed-
collections.html#sec-weakmap-objects)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ Polyfill of ` WeakMap ` in ` core-js ` ](https://github.com/zloirock/core-js#weakmap)
  * [ Keyed collections ](/en-US/docs/Web/JavaScript/Guide/Keyed_collections#weakmap_object)
  * [ Hiding Implementation Details with ECMAScript 6 WeakMaps ](https://fitzgeraldnick.com/2014/01/13/hiding-implementation-details-with-e6-weakmaps.html) by Nick Fitzgerald (2014) 
  * [ ` Map ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map)
  * [ ` Set ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set)
  * [ ` WeakSet ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakSet)

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