Could this be formalised by saying that there should be a function toString such that
fromString . toString = id
There's no such toString for "Maybe a" with fromString = Just.
Sjoerd
On Jul 10, 2013, at 4:02 PM, David Luposchainsky
On 2013-07-10 15:55, Joachim Breitner wrote:
Hi,
Am Mittwoch, den 10.07.2013, 09:21 +1000 schrieb Ivan Lazar Miljenovic:
-0.5 from me; I think it's too easy to forget that it's a Maybe value there when refactoring, etc.
same here; even with OverloadedStrings Haskell should feel as strongly typed as it is.
Agreed. Overloaded strings should be reserved for things that *are* strings in a certain way. A "Maybe String" is not a special way of storing a string (like for example a "Vector Char"), it's a String with an additional value. Providing a Maybe instance goes too far in the direction of having a general "'return' with strings" function, so I'm -1 on this.
David
_______________________________________________ Libraries mailing list Libraries@haskell.org http://www.haskell.org/mailman/listinfo/libraries