ch the source property did not exist.

js

    
    
    const arrayLike = {
      length: 3,
      unrelated: "foo",
      2: 4,
      3: 33, // ignored by reverse() since length is 3
    };
    console.log(Array.prototype.reverse.call(arrayLike));
    // { 0: 4, 3: 33, length: 3, unrelated: 'foo' }
    // The index 2 is deleted because there was no index 0 present originally
    // The index 3 is unchanged since the length is 3
    

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-array.prototype.reverse  ](https://tc39.es/ecma262/multipage/indexed-
collections.html#sec-array.prototype.reverse)  
  
##  Browser compatibility

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

##  See also

  * [ Polyfill of ` Array.prototype.reverse ` in ` core-js ` ](https://github.com/zloirock/core-js#ecmascript-array)
  * [ Indexed collections ](/en-US/docs/Web/JavaScript/Guide/Indexed_collections) guide 
  * [ ` Array ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array)
  * [ ` Array.prototype.join() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/join)
  * [ ` Array.prototype.sort() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort)
  * [ ` Array.prototype.toReversed() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/toReversed)
  * [ ` TypedArray.prototype.reverse() ` ](/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray/reverse)

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