pharo conditionals example

whileMatchesDo.st

whileMatches: aStream do: aBlock
	"Execute block, passing in this instance, for every match in stream.
	
Be extra careful about successful matches which consume no input.
After those, make sure to advance or finish if already at end."

	| wholeMatch reachedEnd |
	reachedEnd := false.
	[ self searchStream: aStream ]
		whileTrue: [ wholeMatch := self subexpression: 1.
			wholeMatch size = 0
				ifTrue: [ aStream atEnd
						ifTrue: [ reachedEnd := true ]
						ifFalse: [ aStream next ] ].
			reachedEnd
				ifTrue: [ ^ self ]
				ifFalse: [ aBlock value: self ] ]