Learn to Code With JavaScript

Chapter 13: Let’s Get Functional

We covered functions back in Chapter 8, but now it’s time to dig a bit deeper and look at some more advanced topics specific to JavaScript.

In this chapter, we’ll be covering the following:

• named parameters
• the rest operator
• hoisting
• scope
• recursive functions
• closures
• functional programming
• pure functions

Named Parameters

When a function has quite a few parameters, it can be difficult to remember what order to write the arguments in when you call the function. For example, consider this function that returns a styled <div> element:

function heading(text,color,size,bgcolor){
  return `<h1 style='color:${color};background-color:${bgcolor};font-size:${size}>${text}</h1>`
}

This uses positional parameters, which ...