# Fibonacci Number
#
# Computes the `n`th iteration of the Fibonacci sequence.
fn fib(n: Number): Number
  var iters = 0
  var low = 0
  var high = 1
  while iters < n
	iters = iters + 1
    let old_low = low
	low = high
	high = low + old_low
  end
  low
end

print fib(10) # => 55
print fib(0) # => 0
print fib(1) # => 1
print fib(11) # => 89