On 9 Aug 2007, at 8:41 am, David Roundy wrote:
I may be stating the obvious here, but I strongly prefer the do
syntax.
It's nice to know the other also, but the combination of do
+indenting makes
complicated code much clearer than the nested parentheses that
would be
required with purely >>= syntax.
Er, what nested parentheses would those be?
do e => e
do e => e >>
rest rest'
do p <- e => e >>= \p ->
rest rest'
do let d => let d in
rest rest'
We get extra >>, >>=, \, ->, and "in" tokens, but no new parentheses.
The example in the Report makes this clear:
do putStr "x: "
l <- getLine
return (words l)
desugars to
putStr "x: " >>
getLine >>= \l ->
return (words l)
with no extra parentheses.
[Not that this actually works in GHC 6; the implied flush isn't done.]
_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe
