[Haskell-cafe] Usage of . and $

Nicolas Frisby nicolas.frisby at gmail.com
Wed Mar 7 17:11:22 EST 2007


> I don't use rank-2 types that often and when I do I'm aware of the
> restriction on ($) and similar hofs. I tend to use ($) only when the
> right-hand side gets very messy; a multiple-line do or similar. For
> example:
>
> blah = fromMaybe $ do
>   x <- blah1
>   y <- blah2
>   guard (x == f y)
>   g x
>
> The closing parenthesis would make things a little messy, so ($) is nice.
>
> -David House, dmhouse at gmail.com

For this situation, I go ahead and name the subcomputation with a
where clause or a do-let binding. Usually, naming sub terms can't
hurt.

Other than "look at Darcs or GHC", has there been any efforts for
(very general, libertarian even) coding guidelines? "Suggestions &
tips" might be a better word.


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