String interpolation

What if we would like to actually print those results? 

First, as you may have already noticed, in one of the examples above, Kotlin provides a nifty println() standard function that wraps the bulkier System.out.println() from Java.

But, more importantly, as in many other modern languages, Kotlin supports string interpolation using the ${} syntax. Following on from the example before:

println("I would suggest: ${suggestGift(10)} ")

The preceding code would print: 

I would suggest: a book

If you're interpolating a variable, and not a function, curly braces could be omitted: 

val gift = suggestGift(100)
println("I would suggest: $gift ")

This would print the following output:

I would suggest: a guitar