This review covers:
• Functions + JSON/Arrays
• Array Manipulations
• JSON
• Map and filter
• Arrow functions
As we know by now, arrays are collections of values.
As we will see, there are often many ways to achieve the same thing when working arrays. Over time, you will add different techniques to your mental toolbox to achieve the result you want quickly.
The array methods map() and filter() are best understood by looking at how they could be implemented if we were to write them ourselves. In the next few sections we will present simplified versions of the native implementations. We have prefixed the method names with my to distinguish them from the built-in versions.