different flavours of Monad Transformer Library

Ross Paterson ross at soi.city.ac.uk
Mon Jan 5 07:49:18 EST 2009

On Mon, Jan 05, 2009 at 01:43:14PM +0100, Henning Thielemann wrote:
> On Mon, 5 Jan 2009, Ross Paterson wrote:
>> 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?

Hugs should be OK: it won't complain about a conflict, and the modules
of the same name will be compatible.  I don't think any other compilers
support functional dependencies, so they would have no mtl to preserve.

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