[Haskell-cafe] new recursive do notation (ghc 6.12.x) spoils layout
John Lask
jvlask at hotmail.com
Mon Jun 21 13:18:19 EDT 2010
Whilst I have nothing against the change in syntax for recursive do aka
http://old.nabble.com/Update-on-GHC-6.12.1-td26103595.html
Instead of writing
mdo
a <- getChar
b <- f c
c <- g b
putChar c
return b
you would write
do
a <- getChar
rec { b <- f c
; c <- g b }
putChar c
return b
it does spoil the nice layout - it would be nice to just be able to
write (which does not parse)
do rec
a <- getChar
b <- f c
c <- g b
putChar c
return b
I don't particularly care that the only recursive statements are #2,#3 -
I just want my nice neat layout back. I have just spent an inordinate
amount of time updating code when if the parser recognised "do rec" as a
recursive group it would have been a drop in replacement and taken me
one tenth of the time.
Why can't we have this?
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