Setting default arguments with JavaScript arrow functions
Yesterday, we looked at how to set default values for JavaScript function arguments.
With arrow functions, it’s even easier.
You can set a default value for each argument at the time that you give it a name with = value
.
// Setting defaults with a traditional function
var add = function (num1, num2) {
// If num1 or num2 aren't defined, set them to 0
num1 = num1 || 0; // conditional operator
num2 = num2 ? num2 : 0; // ternary operator
// Add the numbers
return num1 + num2;
};
// Setting defaults with an arrow function
var add = (num1 = 0, num2 = 0) => num1 + num2;
Arrow functions aren’t production-ready at the moment—they require a compiler to have good enough browser compatibility—but this is still a great feature.
If you like this post, you might also enjoy my vanilla JS pocket guide on variables, functions, and scope.