Does `return` Stop a `forEach` Loop's Iteration?

How Does return Affect the forEach Function's Iteration?

When using the forEach function, you might expect that returning a false value would break out of the loop and stop further iterations. However, this isn't the case.

The Meaning of return in forEach

In the forEach function, the return keyword operates differently than in other loops. Instead of stopping the entire loop, it only returns the current iteration's result.

Example:

Consider the following JavaScript code:

$('button').click(function () {
   [1, 2, 3, 4, 5].forEach(function (n) {
      if (n == 3) {
         // it should break out here and doesn't alert anything after
         return false
      }
      alert(n)      
   })
})

Explanation:

When the iterator function encounters n == 3, it returns false. This does not terminate the entire loop but rather indicates that the current iteration should return false.

Why It Continues Iterating:

The forEach function ignores the returned value and continues iterating through the remaining array elements. This is because forEach is designed to iterate over the entire array, regardless of the results of the iterator function.

Alternative Looping Options:

If you need to break out of a loop conditionally, consider using alternative looping methods such as:

• Simple loop
• for...of loop
• Array.prototype.every()
• Array.prototype.some()
• Array.prototype.find()
• Array.prototype.findIndex()

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