Rosetta Code Fibonacci Example

From rosettacode.org:

Code Examples

Using Recursion

Code to calculate fibonacci numbers using a recursion:

fib(n i32) i32 is if n < 2 n else fib n-1 + fib n-2 for i in 0..20 do say (fib i)

Using Loop

Code to calculate fibonacci numbers using a loop:

fib(n i32) => for a := 0, b b := 1, next next := a + b i in 1..n else a for i in 0..20 do say (fib i)

Supporting Negative Fibonacci Numbers

Code to calculate fibonacci numbers including negative ones using a loop:

fib(n i32) => for dir := n.sign // -1, 0 or +1 a := 0, b b := dir, next next := a + b i in dir..n : dir else a for i in -10..10 do say (fib i)