Re: enforcement of context constraints

1991-11-29 Thread haskell-request
Original-Via: uk.ac.nsf; Fri, 29 Nov 91 19:37:26 GMT X-Comment1: # X-Comment2: # uk.ac.glasgow.cs has changed to uk.ac.glasgow.dcs # X-Comment3: # If this address does not work please ask your mail # X-Comment4: # administrator to update

Re: enforcement of context constraints

1991-11-26 Thread haskell-request
Original-Via: uk.ac.nsf; Tue, 26 Nov 91 02:54:29 GMT If I have understood you correctly, there is not a problem. If there is an instance declaration for class C and type T, it must occur either in the module that declares C or the module that declares T, and is exported whenever C or T is expor

enforcement of context constraints

1991-11-23 Thread haskell-request
Original-Via: uk.ac.nsf; Sat, 23 Nov 91 08:53:36 GMT I am confused about the meaning of constraints imposed by a context. I will try to illustrate my understanding with an example. I am hoping that the Gurus will either confirm or give another explanation. Suppose I define f x y z = if