JavaScript if shorthand without the else

At one point in your career, you'll find yourself using the ternary operator in JavaScript a lot.

It's a fancy word for the if...else shorthand version.

Let's recheck the example.

// Full if elselet result = '';if (our_value) {  result = 'we got a value';} else {  result = 'no value';}// Ternaryresult = our_value ? 'we got a value' : 'no value';

So that's already a set working example.

If without the else

However, sometimes we might want to execute or set something if a specific condition is met.

Let's look at the following example.

if (our_value) {  alert('I have the value');}

This piece of code should alert the user if the our_value condition is truthy.

There is no else involved.

We could write it like this:

our_value ? alert('I have the value') : null;

However, we don't need the null value as it doesn't do anything, so we can switch to using the && operator.

our_value && alert('I have the value');

Way cleaner, we tell the script if we do have this truthy value, we should alert the user.

Nullish default value

In some cases, you might have a function that returns some value, but you might want to return a default value if the object is nullish.

const name = null;const user = {  username: name ? name : 'John Doe',};console.log(user);// { username: 'John Doe' }

That example works perfectly fine. However, it's a bit duplicated again. We can leverage the ?? operator to set a default return value.

This ?? operator is called a logical nullish operator.

const user = {  username: name ?? 'John Doe',};

This will either return the value of name, and if that doesn't exist, it will return John Doe.

Note: Be careful when the value can be false as it will return false in that case.