If you want to make it safer you could use ``` val zero = 0 kotlinlang #getting-started

If you want to make it safer, you could use: ``` v...

Ruckus

05/03/2017, 10:09 PM

If you want to make it safer, you could use:

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val zero = '0'.toInt()
val digits = '0'..'9'
fun String.calc() = map { require(it in digits); it.toInt() - zero }.reduce(Int::times)