-Wall -Werror

Simon Peyton-Jones simonpj at microsoft.com
Tue Aug 12 03:11:41 EDT 2008


| Duncan Coutts wrote:
| >> $ head -1 time/Data/Time/Calendar/Gregorian.hs
| >> {-# OPTIONS -Wall -Werror #-}
| >>
| >> (in actual fact, we don't even build GHC/bootlibs with -Werror except
| >> when validating).
| >
| > Ah, so that's the culprit.
| I prefer this, actually, as we get to discover issues sooner rather than
| later. Though putting it in the .cabal file or wherever might be better.

That's fine.  But then you can choose

a) add -fno-warn-orphans
b) move the (Show Day) instance to the module declaring Day.

I'm not sure which is best for you, but you're the package author so you get to decide!

Regardless, it'd help if you felt able to do one or the other, because currently the package won't compile at all.


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