// [Function: set foo]
    

js

    
    
    const obj2 = {
      __proto__: {
        set foo(value) {
          this.bar = value;
        },
      },
    };
    
    function findSetter(obj, prop) {
      while (obj) {
        const desc = Object.getOwnPropertyDescriptor(obj, prop);
        if (desc) {
          return desc.set;
        }
        obj = Object.getPrototypeOf(obj);
      }
    }
    
    console.log(findSetter(obj2, "foo")); // [Function: set foo]
    

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-object.prototype.__lookupSetter__
](https://tc39.es/ecma262/multipage/additional-ecmascript-features-for-web-
browsers.html#sec-object.prototype.__lookupSetter__)  
  
##  Browser compatibility

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

##  See also

  * [ Polyfill of ` Object.prototype.__lookupSetter__ ` in ` core-js ` ](https://github.com/zloirock/core-js#ecmascript-object)
  * [ ` Object.prototype.__lookupGetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/__lookupGetter__)
  * [ ` set ` ](/en-US/docs/Web/JavaScript/Reference/Functions/set)
  * [ ` Object.getOwnPropertyDescriptor() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/getOwnPropertyDescriptor)
  * [ ` Object.prototype.__defineGetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/__defineGetter__)
  * [ ` Object.prototype.__defineSetter__() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/__defineSetter__)
  * [ JS Guide: Defining Getters and Setters ](/en-US/docs/Web/JavaScript/Guide/Working_with_objects#defining_getters_and_setters)

##  Help improve MDN

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