Hi, I am using a nice little method #destructDo: for a while now and it feels good. In VisualWorks: SequenceableCollection>>destructDo: aBlock "Evaluate aBlock with the receiver's elements as parameters. aBlock takes its arguments from the receiver. 'ok' #(1 2 3) destructDo: [:a :b :c | a + b + c] #(1 2 3) destructDo: [:a :b | a + b] #(1 2 3) destructDo: [:a | a] #(1 2 3) destructDo: [42] 'not ok' #(1 2 3) destructDo: [:a :b :c :d | a + b + c + d] " ^aBlock cullWithArguments: self asArray In Amber: SequenceableCollection>>destructDo: aBlock ^aBlock valueWithPossibleArguments: self In Pharo and other dialects, I don't know, but should be as easy. For example you can do (('2020-03-28' tokensBasedOn: $-) collect: #asNumber) destructDo: [:year :month :day | Date newDay: day monthNumber: month year: year] I like that the block is not the receiver (like with #valueWithArguments or #cullWithArguments), but the last argument. Now the questions: * I am sure that others came up with this. Anybody knows? * What are you using for this pattern? * I don't really like the name, but haven't found anything better yet. Maybe #destructedDo: or just #destructed: or: #withPartsDo:. maybe something shorter? Ideas? * What are you thinking about this? Happy hacking, Christian