> splitOn: aString
> 
>     | idx lastIdx |
>     idx := lastIdx := 1.
> 
>     ^Array streamContents:
>     [:s |
>         [idx <= self size] whileTrue:
>         [
>             idx := self findString: aString startingAt: lastIdx.
>             idx = 0 ifTrue: [idx := self size + 1].
>             s nextPut: (self copyFrom: lastIdx to: idx-1).
>             lastIdx := idx + aString size.
>         ]
>     ]

Cool, thanks.