2014-09-03 14:40 GMT+02:00 Marcus Denker <[email protected]>: > with:do: on SequencableCollection checks that both collections have the > same size (it raises an Error if not). > > with: otherCollection do: twoArgBlock > "Evaluate twoArgBlock with corresponding elements from this collection > and otherCollection." > otherCollection size = self size ifFalse: [self error: > 'otherCollection must be the same size']. > 1 to: self size do: > [:index | > twoArgBlock value: (self at: index) > value: (otherCollection at: index)] > > I think we should not do that: > > 1) it is slow >
Are you sure about that one? The check is a constant cost disregarding the collection length, and, anyway, self size is reused just after that. > 2) when the other is larger, is would work and just omit the rest 3) if it is smaller, you will get an error anyway > I have a feeling I'm not in Pharo anymore, but in R instead ;) Thierry > > There are just three methods doing such a size check: > > with:do: > with:collect: > reverseWith:do: > (the last one actually raises a SizeMismatch exception, it is the > sole user of that exception) > > Is there a reason why this makes sense? > > I added an issue with a slice to clean it up: > > > https://pharo.fogbugz.com/f/cases/13946/speed-up-with-do-by-not-checking-size > > Marcus > > > > > >
