MR K P SCHUPKE k.schupke at
Wed Oct 13 09:05:56 EDT 2004

What is the situation with deriving?

Some instances can be derived automatically for both data/newtype (built in)?

Some instances cen be derived automatically for newtype (any)?

You used to be able to define functions useing {|+|} and {|*|} (or similar)
that could be derived for both data and newtype.

What is the current status, which methods are supported, and will be
supported going forward.

I ask this because looking at the code in the compiler it seems very
difficault to extend. It would be to specify how to derive new instances
once and for all...


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