[Haskell-beginners] recursive 'let' ?

Arjun Comar nrujac at gmail.com
Mon Apr 14 20:04:32 UTC 2014


John,
That's classic mutual recursion. In your example, the values of b and c
depend entirely on f. For example what if

    f = const a

Now b and c are obviously a and its not ambiguous. Similarly, mutually
recursive functions can compute values for b and c.

Do you have a similar issue with a definition like:

    b = f a b

or is that fine? If so, why? If not, why not?


On Mon, Apr 14, 2014 at 11:24 AM, John M. Dlugosz
<ngnr63q02 at sneakemail.com>wrote:

> I don't mind recursive *functions*.  It's recursive definition of single
> computed values that looked odd to me.  Lazy evaluation makes all the
> difference.  Looking at
>         b= f a c
>
>         c = f a b
> I was thinking, "how can it figure out what b and c need to be?" because
> I'm used to this meaning that it needs to come up with an actual value
> right now.
>
>
>
>
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