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Next, suppose that you want to define factorial, a method that answers
n!, where the receiver is to be an integer, n, and
n! =n * n-1 * ... * 1. As in the calculation
performed by powerOfTwo, repeated multiplication is involved, but
this time the multipliers are not all the same.
You could define factorial using timesRepeat, albeit awkwardly:
Integer method definition • instance factorial | result multiplier | result := 1. multiplier := self. self timesRepeat: [result := result * multiplier. multiplier := multiplier - 1]. ^ result Workspace Transcript show: 4 factorial printString Transcript 24