Hi all do we agree that the following is the semantics of flatCollect: testCollectUnion self assert: ((#((1 2) (3 4) (5 3)) collectUnion: [ :each ]) equalsTo: #(1 2 3 3 4 5)). self assert: ((#((1 2) (2 3) (1 3 4)) collectUnion: [:each]) equalsTo: #(1 1 2 2 3 3 4)). self assert: ((#() asCollection collectUnion: [:each]) equalsTo: #() asCollection) true. self assert: ((#() asCollection collectUnion: [:each]) equalsTo: #() asSet). self assert: ((#((1 2) (1 2) (1 3 4)) asSet collectUnion: [:each]) equalsTo: #(1 1 2 3 4) asSet). self assert: ((#() asSet collectUnion: [:each]) equalsTo: #() asSet). we happen the results of the collect. Like a mapcan in LISP. Is it ok for you? Stef _______________________________________________ Moose-dev mailing list Moose-dev(a)iam.unibe.ch https://www.iam.unibe.ch/mailman/listinfo/moose-dev