Am 13.08.2013 23:18, schrieb MightyByte:
For me, the name EitherT wins by a large margin. Way back when I first learned about MaybeT, it totally rocked my world. I had been plagued for quite some time by the problems that MaybeT addresses but didn't know of the solution. I had already seen things like ReaderT and StateT, but for some reason I hadn't yet made the connection to how the idea would carry over to the Maybe monad. After I learned about MaybeT, EitherT was the natural name I expected. If EitherT had been in transformers, I think I would have used it even sooner.
I think the discoverability of the name EitherT is huge win given the existing conventions. I think I had even seen ErrorT before MaybeT, but the name obscured its significance for me.
1. You discovered Either as a monad first, which I think is the initial problem. Either should never have been abused for exception handling and it should never have been a monad. If Either would not be a monad then no-one would look for EitherT. 2. Now since Either is a monad and people are looking for EitherT, it would be simple to note that in the documentation of ExceptT. One could even upload a new version of "EitherT" and "either" packages that redirects people to ExceptT.