Short Circuit Conditionals With Logical AND(&&) Operator - JavaScript

The short circuiting was meant to stop the further execution based on boolean operations. With Logical AND(&&) operator, if the false value of expression has already been determined than further execution will not happen.

Precedence for Logical AND is from left to right.

Example

Let us consider, we’ve an application on our device which uses Unsplash API to retrieve data from it. If the device is not connected to internet, then no data will not be fetched.

navigator.onLine

We will be using navigator.onLine property to verify whether the user is connected to the internet or not.
The navigator.onLine property return true if connected to internet else false.

Example using if condition

if (navigator.onLine) {
  fetchUnsplashImages();
}

Example using short circuit conditional

  navigator.onLine && fetchUnsplashImages();

Now the code is just a single line navigator.onLine && fetchUnsplashImages();. Here the fetchUnsplashImages() function only executes when navigator.onLine return true i.e user is connected to internet.

Happy coding

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