On Thu, Jan 9, 2014 at 11:52 AM, Vlatko Basic
... what exactly is the problem with using appropriate data types in appropriate places ... It is a good thing. Very good. But I do not think all library writers are using it in correct places. But that's another problem.
In Haskell it's even a solved one: use an appropriate typeclass. We have several error-like typeclasses. Admittedly, if some library does not take advantage of this your recourse may be to submit a patch. And you still seem to be fixated on the notion that Maybe is only for errors. What exactly is the error in "user did not provide an optional parameter"? -- brandon s allbery kf8nh sine nomine associates allbery.b@gmail.com ballbery@sinenomine.net unix, openafs, kerberos, infrastructure, xmonad http://sinenomine.net