[Haskell] How to close a type class

Marcin 'Qrczak' Kowalczyk qrczak at knm.org.pl
Fri Nov 12 06:19:45 EST 2004


oleg at pobox.com writes:

> Thus we have reduced the problem of excluding certain types from a
> typeclass to the problem of excluding all types from one particular
> typeclass: Fail. How can we prevent the user from adding instances to
> Fail?

By not exporting its name?

-- 
   __("<         Marcin Kowalczyk
   \__/       qrczak at knm.org.pl
    ^^     http://qrnik.knm.org.pl/~qrczak/


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