I want to vote, too. I am ok with all of case of \case \of \case of For me single arguments are enough. We already have this restriction for 'case' and I can work around it simply by wrapping arguments in pairs temporarily (cf. curry $ \case ...). I vote against LambdaIf, since if-then-else is already unnecessary and can be written by ifThenElse, and LambdaIf is just ifThenElse with different parameter order. I vote against MultiCaseIf since it can be simply achieved by ifThenElse b1 a1 $ ifThenElse b2 a2 $ ifThenElse b3 a3 $ a4 http://www.haskell.org/haskellwiki/Case