Enum class

Ch. A. Herrmann herrmann@infosun.fmi.uni-passau.de
Tue, 23 Oct 2001 10:57:20 +0200


Hi Haskellers,

assuming that the type class "Enum" represents enumeration
types, there are two questions for me:

(1) What is the justification for the types "Float" and "Double"
    to be members of the type class "Enum"? This might induce students
    to use floating point values as counters in arithmetic 
    sequences. 

(2) Why not make tuples of bounded enumeration types 
    themselves bounded enumeration types? E.g.,

       [(False,False)..(True,True)] 

    could evaluate to

       [(False,False),(False,True),(True,False),(True,True)]

    and it is comprehensible since the ordering in the sequence
    equals the lexicographic ordering imposed on tuple comparison.

Cheers
Christoph