Glad to hear.
The next step was supposed to be moving a few instances out of
the either library and deprecating that library. Is that no longer planned?
Whether or not it will be deprecated, a prominent note about this
really should be added to the package description of the either
library.
And a note should be added to the module description of
Control.Monad.Trans.Except that throwing exceptions is only
one of many uses for this monad. I frequently use (the old
either library version of) this monad for complex conditional
logic and early exit from computations, at least as often as
I use it for throwing exceptions.
Thanks,
Yitz
On Mon, Dec 29, 2014 at 12:29 AM, Roman Cheplyaka
It is already merged (under the name of ExceptT).
On 28/12/14 23:14, Yitzchak Gale wrote:
Roman Cheplyaka wrote in February 2014:
I proposed to merge either into transformers more than a year ago[1], and everyone seemed to agree. Could you please do it?
[1]: http://www.haskell.org/pipermail/libraries/2012-December/019027.html
Ross Paterson responded:
Not everyone agreed when we discussed this last August. My proposal then was to introduce a new constructor ExceptT on the same pattern as ReaderT, etc, and to deprecate ErrorT, and that's what I intend to include in the next major release, after GHC 7.8 comes out.
First of all, GHC 7.8 is well past. Now we are well into the 7.10 zone.
I re-read the original thread and did not find anyone who disagreed with this, so I'm not sure what you mean by that.
I also didn't find any mention of ExceptT there. The discussion was about merging the either library into transformers as is, with the bits that are problematic due to non-base dependencies written out by hand where possible or else omitted.
That said, I think everyone will support you, without bikeshedding, if you decide to change any of the names and/or deprecate ErrorT.
Thanks, Yitz