Conditional (Ternary) Operator in JavaScript Guide

By Piotr Sikora

development

Let's imagine that we could optimize / minify if statement. What could we do?

In case we have if...else statement like:

if (condition) {
// do sth if condition is true
}
else {
// do sth else if condition isn't true
}

we can change it to ternary expression

condition ? /* do sth if condition is true */ : /* do sth if condition isn't true */;

Let's check how it works with functions:

const actionOne = () => console.log('actionOne');
const actionTwo = () => console.log('actionTwo');

true ? actionOne() : actionTwo(); // actionOne
false ? actionOne() : actionTwo(); // actionTwo

And how to use it with more complex functions:

const multiply = (a) => a*a;
const add = (a) => a+a;

const variable = 4;

let newVar;

newVar = true ? multiply(variable) : add(variable);

console.log(newVar) // 16

newVar = false ? multiply(variable) : add(variable);

console.log(newVar) // 8