Re: [Haskell-cafe] lambda case

Right, case..of is superfluous, case e of branches can now be written as e |> \case branches with backwards application |> (or some prefer & --- sadly, the proposal to add backwards appliation to base did not make it to a consensus). This is in accordance to the monadic me >>= \case branches If there was an opportunity to make drastic language changes, case..of could be disposed of altogether. \case could become 'cases' or 'match' or 'fun' (rather not 'of', for my taste). The current compromise it not too bad, I think. Unfortunately, I have to wait for 7.6 to become the standard before using \case in Agda source... Cheers, Andreas On 30.11.12 7:25 AM, Herbert Valerio Riedel wrote:

Jon Fairbairn writes:

[...]

...

“\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

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