flatMap, concatMap – In details

As promised in the previous chapter, now we will take a deeper dive into the flatMap and concatMap operators, as, by now, we have already gained some sort of expertise on the merge and concat operators and know the differences between them.

Let's start with the differences between flatMap and concatMap, after which, we will also discuss their ideal implementation scenarios. We will also discuss some of their variants to know them better.

In the previous chapter, we mentioned that flatMap internally uses the merge operator and concatMap internally uses the concat operator. However, what difference does that make? You just learned the differences between the merge and the concat operator, but what is the point of having two separate mapping operators based on them? So, let's start with an example. We will see an example with flatMap, and then we will try to implement the same with concatMap:

    fun main(args: Array<String>) { 
      Observable.range(1,10...