Jon Fairbairn
“\case” complicates lambda, using “of” simply breaks “case … of …” into two easily understood parts.
Just some observation (I'm rather late to the lambda-case discussion, so this might have been already pointed out previously): if the reserved keyword 'of' was to take the place of '\case', shouldn't then 'case' exp w/o the "'of' { alts }"-part become a separately valid expression (with 'case' essentially meaning 'flip ($)') to really break it up into two independent parts? Then 'case exp of { alts }' wouldn't be a special form anymore, but would just result from combining 'case' and 'of'; 'case' wouldn't even need to be a reserved keyword (and thus the grammar could be simplified), if it wasn't for the current grammar which requires to isolate a \case-expression by using () or $, consider e.g.: {-# LANGUAGE LambdaCase #-} import System.Environment case' :: b -> (b -> c) -> c case' = flip ($) main = do s <- getArgs case' s $ \case -- image '\case' was actually '\of' or 'of' [x] -> putStrLn ("Hello " ++ x) _ -> putStrLn "wrong number of arguments given" just my 2¢ cheers, hvr