d
setters will be invoked.

js

    
    
    class X {
      constructor() {
        // Create a non-writable property
        Object.defineProperty(this, "prop", {
          configurable: true,
          writable: false,
          value: 1,
        });
      }
    }
    
    class Y extends X {
      constructor() {
        super();
      }
      foo() {
        super.prop = 2; // Cannot overwrite the value.
      }
    }
    
    const y = new Y();
    y.foo(); // TypeError: "prop" is read-only
    console.log(y.prop); // 1
    

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-super-keyword  ](https://tc39.es/ecma262/multipage/ecmascript-language-
expressions.html#sec-super-keyword)  
  
##  Browser compatibility

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

##  See also

  * [ Classes ](/en-US/docs/Web/JavaScript/Reference/Classes)

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