Course of Raku / Functional, concurrent, reactive, and web programming / Functional programming / Lambdas and closures / Exercises
A counter
Problem
Write a subroutine make-counter($step) that returns a
closure. Each time the closure is called, it advances a running total by
$step and returns it. The closure must remember both the
step and the total. Create a counter with a step of 10 and
print its first three values.
Example
The program prints:
10
20
30