2010/7/2 Nicolas Cellier <nicolas.cellier.aka.n...@gmail.com>: > 2010/7/2 Simon Denier <simon.den...@inria.fr>: >> I just noticed that the semantic of Collection>>ifNotEmpty: has changed in >> subtle ways between Pharo 1.0 and 1.1 >> >> In 1.0 >> Collection>>ifNotEmpty: aBlock >> "Evaluate the given block unless the receiver is empty. >> >> If the block has an argument, eval with the receiver as its argument, >> but it might be better to use ifNotEmptyDo: to make the code easier to >> understand" >> >> ^self isEmpty ifFalse: [aBlock valueWithPossibleArgument: self]. >> >> -----> it returns nil if collection is empty >> >> >> in 1.1 >> Collection>>ifNotEmpty: aBlock >> "Evaluate the given block unless the receiver is empty. >> >> If the block has an argument, eval with the receiver as its argument, >> but it might be better to use ifNotEmptyDo: to make the code easier to >> understand" >> >> self isEmpty ifFalse: [^ aBlock valueWithPossibleArgument: self]. >> >> ----> the return is inside the block, now it returns the collection if >> collection is empty >> >> >> Apparently all similar code (#ifEmpty:....) has been adapted in the same way. >> >> Of course I would not have stumbled upon this change if it didn't break some >> of my code which rely on the previous assumption. >> >> Now I would like to understand before making some change in my code. Is it >> considered bad practice to return nil in such cases? What is the rationale >> to return yourself instead of nil? >> > > The new version is better because: > - it is homogeneous with ifNil: behaviour > - it enables writing: self classifyMethodAs: (myProtocol ifEmpty: > ['As yet unclassified']) > > Nicolas >
Oops, embarassing, I didn't answer the good question :( Maybe it's homogeneous with ifNotNil: ? Nicolas >> -- >> Simon >> >> >> >> _______________________________________________ >> Pharo-project mailing list >> Pharo-project@lists.gforge.inria.fr >> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >> > _______________________________________________ Pharo-project mailing list Pharo-project@lists.gforge.inria.fr http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
