Fibonacci numbers in Smalltalk

Example for versions Squeak 3.10

This code is a method of an object, and adds n Fibonacci numbers to an OrderedCollection called numbers.

Variable declarations are enclosed in vertical bars and don’t specify their type. Code blocks are enclosed in square brackets. The “^” carrot at the end returns the result from this method. 

fibonacci: n
    | numbers a b |
    numbers := OrderedCollection new.
    a := 1.
    b := 1.
    [ numbers size < n ] whileTrue: [
	| temp |
	numbers add: a.
	temp := b.
	b := a + b.
	a := temp.
    ].
    ^ numbers.