On Fri, Jan 21, 2011 at 3:37 AM, Simon Michael <simon@joyful.com> wrote:
You mean mtl 2.*, right ?

Yes that is a problem. I'm nervous about requiring mtl 2 because when I bumped hledger 0.13's process dependency to 0.14 for similar reasons it made all kinds of trouble for folks who just want to install the hledger core in standard/older haskell environments.

Well, chalk me up as the person with standard/old haskell environment :)
I have many versions of GHC installed, plus I have a Haskell Platform from .debs as provided by Debian/unstable. That version of HP still carries GHC 6.12.1 and mtl 1.*

Using that, it is impossible to "make install" hledger for the reasons outlined below - you either have to exclude hledger-chart, or build fails.
 


On Jan 20, 2011, at 5:11 PM, Dmitry Astapov wrote:
Since hledger-chart depends on Chart, which in turn depends on transformers 0.2.*, it will make a sense to bump all mtl dependencies in hledger to 2.2

When one does "make install" with older GHC (like 6.12.1, for example), and mtl 1.x is available, it would be happily used for hledger-lib and hledger, but compilation of hledger-chart will pull in transformers 0.2 (but not the newer mtl) and will fail due to conflicting instances.




--
Dmitry Astapov