different flavours of Monad Transformer Library

Henning Thielemann lemming at henning-thielemann.de
Mon Jan 5 07:43:14 EST 2009


On Mon, 5 Jan 2009, Ross Paterson wrote:

> On Mon, Jan 05, 2009 at 12:54:20PM +0100, Henning Thielemann wrote:
>
>> Since mtl-split is not a drop-in replacement for mtl, we cannot expect a
>> quick change from mtl to mtl-split in all the packages that currently
>> import mtl. Thus we have to think about a route of transition and a
>> package which can be installed in parallel to mtl is a first step, I
>> think.
>
> My understanding is that GHC will allow both to be installed, and allow
> packages that use transformers and those that use mtl to be used together
> in the same program.  What you can't do is use both transformers and
> mtl directly in the same package, but that's no big loss.

If this is true, then I will no longer complain. What about Hugs and 
others?


More information about the Libraries mailing list