Why is \"options = options || {}\" Used in JavaScript?

Demystifying "options = options || {}" in JavaScript

Enhancing the understanding of JavaScript enthusiasts, this article delves into the enigmatic code snippet:

options = options || {};

Purpose Revisited

This line of code effectively establishes default values for function arguments. Consider the following function:

<code class="javascript">function test(options) {
  options = options || {};
}</code>

When invoked without any arguments, the options parameter automatically initializes as an empty object.

Logical OR Operator Explained

The crux of this operation lies in the logical OR (||) operator. It yields the second operand if the first operand is "falsy."

"Falsy" values include 0, null, undefined, empty strings (""), NaN, and false.

ES6 Evolution

JavaScript ES6 introduced default parameter values, streamlining this process:

<code class="javascript">function test(options = {}) {
  //...
}</code>

In this case, invoking the function without arguments or explicitly passing undefined assigns the default value to the options argument. Unlike the || operator, other falsy values do not trigger the use of the default value.

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