n+k patterns

[Olaf Chitil]

> In any case,  I propose to change "Integral" to "Ord and Num".

I agree. And nhc98 seems to actually implement this.
Nonetheless I find using n+k patterns for floating point numbers pretty
horrible. And it raises the question why k cannot be a rational ...
But then n+k patterns are a wart anyway.

Btw., in 3.17.2  Informal Semantics of Pattern Matching
the end of the following sentence should be changed:

Matching a non-_|_ value x against a pattern of the form n+k (where n is
a variable and k is a positive integer literal) succeeds if x>=k,
resulting in the binding of n to x-k, and fails if x<k. 

There is no guarantee that if x>=k == False then x < k == True.
So the sentence should end "..., and fails otherwise".

Olaf

-- 
OLAF CHITIL, 
 Dept. of Computer Science, The University of York, York YO10 5DD, UK. 
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