[Haskell-cafe] Inheritance and Wrappers
Brandon S Allbery KF8NH
allbery.b at gmail.com
Mon Jan 31 21:34:27 CET 2011
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On 1/31/11 15:24 , Daniel Fischer wrote:
> want. You could then also enable OverlappingInstances, which would allow
> you to write other instances, but that extension is widely regarded as
> dangerous (have to confess, I forgot what the dangers were, one was that
> instance selection doesn't always do what you want/expect).
Instance selection will still not look at the context, so multiple instances
would complain about needing IncoherentInstances, and if you add *that* then
it does something like taking the first matching instance it finds (again,
ignoring the context completely).
- --
brandon s. allbery [linux,solaris,freebsd,perl] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university KF8NH
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