Local functions

The idea behind functions is very simple: split up a large program into smaller chunks that can be reasoned more easily and allow the reuse of the code to avoid repetition. This second point is known as the DRY principle: Don't Repeat Yourself. The more the number of times you write the same code, the more the chances you create of a bug creeping in.

When this principle is taken to its logical conclusion, you would have created a program that consists of many small functions, each doing a single thing; this is similar to the Unix principle of small programs, where each program does a single job.

The same principle applies to the code inside a function. Typically, in say Java, a large function or method might be broken down by calling ...

Get Programming Kotlin now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.