[Pharo-users] Robust flatten for collection?

Hi there A question to test your sagacity :) I'm looking for a method which would flatten a collection, regardless of whether the collection is already flat or not. that is: #((1 2 3) (4 5 6)) flatten --> #(1 2 3 4 5 6) #(1 2 3 4 5 6) flatten --> #(1 2 3 4 5 6) #((1 2 3) 4 5 6) flatten --> #(1 2 3 4 5 6) Any idea about the best implementation for this? -- Simon