More typos

[haskell-request]

Original-Via: uk.ac.st-and.cs; Mon, 28 Oct 91 14:54:31 GMT

The functions toUpper and toLower in the standard prelude (p 80) have
initial definitions which should read:

toUpper c | isLower c = chr (ord c - (ord 'A' - ord 'a'))

and

toLower c | isUpper c = chr (ord c - (ord 'a' - ord 'A'))

Tony