There's a weird idiom that I see all the time in Haskell code where coders put commas at the beginning of lines: data Thing = Thing { x :: Int ,y :: Int ,z :: Int ,foo :: String } ... items = [ "red" ,"blue" ,"green" ] and it's pretty clear that the reason for this is that it's easier to comment out the last item by prefixing -- items = [ "red" ,"blue" -- ,"green" ] instead of items = [ "red", "blue" -- , -- "green" ] The same sort of thing shows up with semicolons sometimes too let { x = 1 ;y = 2 ;z = 3 } in However, this punctuation-at-the-front just seems wrong. It ultimately comes from using , as a separator rather than a terminator in the syntax of sequences. But Python has this nifty quirk where you can leave a comma after the last item in a sequence, so that the following is OK in Python but not in Haskell: items = [ "red", "blue", -- "green" ] Part of why Python does this is to allow room in the syntax for tuples with a single item as in (1,) There might be problems doing this with Haskell tuples because of tuple sections like (,,,) building a 4-tuple from 4 arguments, and where (x,y,) is interpreted as a function that takes another item and produces a three-component tuple. Anyway, this is a "paper cut" in the language that has been bugging me for a while, and since there's now a call for suggestions for Haskell 2014, I thought I'd ask about it. -- Garrett Mitchener