That's really unfortunate that using the library is slowing then rolling 
your own. :(


>From: Andreas Raab <andreas.raab at gmx.de>
>Reply-To: The general-purpose Squeak developers 
>list<squeak-dev at lists.squeakfoundation.org>
>To: The general-purpose Squeak developers 
>list<squeak-dev at lists.squeakfoundation.org>
>Subject: Re: Idea for a possibly better Collection occurrencesOf method.
>Date: Mon, 11 Sep 2006 22:03:12 -0400
>
>tim Rowledge wrote:
>>You might possibly be able to measure a small performance cost to using 
>>inject:into: because it passes down to a virtually identical loop (ie uses 
>>a temp, a do: loop etc) and costs you one extra message send or so.  If 
>>someone chose to write the compiler optimiser code to inline inject:into: 
>>then it would not cost even that.
>
>It is also an extra activation per element of the collection (because the 
>ifTrue:-block in the original version gets inlined) which actually shows in 
>a quick benchmark:
>   "Create a list with 1 million true/false elements"
>   list := Array new: 1000000.
>   1 to: list size do:[:i| list at: i put: i even].
>   "Search for occurances of true by various means"
>   anObject := true.
>   tally := 0.
>   time1 := [list do:[:each| anObject = each ifTrue:[tally := tally + 1]]] 
>timeToRun.
>   time2 := [list inject: 0 into: [:tally :each |
>               anObject = each
>                   ifTrue: [tally := tally + 1]
>                   ifFalse: [tally]]] timeToRun.
>   time3 := [list count:[:each| each = anObject]] timeToRun.
>   { time1. time2. time3}
>
>This results in #(397 590 600) on my machine with the significant 
>difference that being between ~400ms (original version) vs. ~600ms (with 
>extra activation).
>
>Cheers,
>   - Andreas
>