Kotlin Programming Cookbook

How to do it…

Follow the mentioned steps to understand how to create a chain of multiple lets:

1. When you have to do multiple null-checks, you can obviously use nested if-else, checking null conditions, as in the following code:

if(variableA!=null){    if(variableB!=null){        if(variableC!=null){            // do something.        }    }}

2. Since we know that the let function guarantees that the block will run only when the object is not-null, we need to create a function that will perform the function of let but on three variable scenarios. Let's take a look at our function:

fun <T1: Any, T2: Any,T3:Any, R: Any> multiLet(p1: T1?, p2: T2?,p3:T3?, block: (T1, T2,T3)->R?): R? {    return if (p1 != null && p2 != null &&p3!=null) block(p1, p2,p3) else null}

3. Now we can use ...