12 Aug
2014
12 Aug
'14
5:34 p.m.
Am 12.08.2014 um 21:17 schrieb Edward Kmett:
so it seems the logical extension of your request would be to strip all such instances,
one by one, please :-) Can someone provide me examples of useful applications of mfix on Maybe, ExceptT etc.? I mean, all those mfix instances contain an "error" - wouldn't it be better if the user would do such dirty things and insert a more specific error message? Admittedly, I have used mfix only once so far, at all, namely on an RWS monad, as far as I remember. Eventually I chose another design, because the mfix way was too fragile.