Memoization for Smalltalk

BlockClosure-memoized.st

'Copyright (c) 2014 John Cromartie

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!BlockClosure methodsFor: '*memoization' stamp: 'JohnCromartie 5/15/2012 18:08'!
memoized
	"returns memoized version of an unary function"
	| cache |
	cache := Dictionary new.
	^ [ :x | cache at: x ifAbsentPut: [ self value: x ] ]! !