Enum class

Lennart Augustsson lennart@augustsson.net
Tue, 23 Oct 2001 11:11:06 +0200


"Ch. A. Herrmann" wrote:

> (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.

And what's wrong with that? If the students are using are using values
like 0.1 and expecting it to be represented exactly then they should have
some lectures about floating point arithmetic.
I've heard your complaint before, but I can't really understand why removing
Float and Double from Enum would make Haskell any better for beginners.
These two type  have complicated properties, and to use them correctly you
have to know about them.  It's something you have to learn sooner or later.
(In the the olden day when I had my first CS course we were told about it
very early.)

    -- Lennart