Simplifying JavaScript

Tip 18

Check Data Quickly with the Ternary Operator

In this tip, you’ll learn how to avoid reassignment with the ternary operator.

By now, you may have noticed that I love simple code. I’ll always try to get an expression reduced down to the fewest characters I can. I blame a former coworker who reviewed some code I wrote at one of my first jobs.

if(active) {
    var display = 'bold'
} else {
    var display = 'normal'
}

He took one glance and casually said, “You should just make that a ternary.”

“Of course,” I agreed, not quite sure what he was talking about. After looking it up, I simplified the code to a one-line expression and my code has never been the same.

var display = active ? 'bold' : 'normal';

Chances are you’ve ...