[Haskell] Re: Please check your dependencies on fgl

Christian Maeder Christian.Maeder at dfki.de
Tue Jun 8 07:34:51 EDT 2010

Ivan Lazar Miljenovic schrieb:
>> Although parsec-3 can be used as an replacement for parsec-2 it would
>> have been better, they had different names (as argued elsewhere for the
>> haskell platform).
> I'm sorry, I don't recall this discussion: care to summarise?


> With fgl, the actual changes aren't that big on the user side of things
> if they want to keep using the defaults (it's not a drop-in replacement,
> but the _way_ to use it remains unchanged).

I usually don't want to make even small changes at installation time.

> The big difference is when people want to make custom instances;
> however, as far as I know no-one has created any custom instances for
> FGL's classes.

Well, I've created a custom instance:
and our hets project is not a hackageDB package.

> But by keeping the old fgl around as a separate package, there is then
> no real incentive to change/upgrade.  If, however, we re-use the package
> name then it will be more obvious that there is a new and (hopefully)
> improved version available.

Your "incentive" would be a "small annoyance" for me since it would
force me to  change the dependency to "fgl < ..." until I find time to
test our code with the newer fgl version (without possible other changes).

(I still haven't updated from tabular- to tabular-0.2.x, yet.)

Cheers Christian

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