[Haskell-beginners] What is the Haskell idiom for "if then else if then"

Paul Visschers mail at paulvisschers.net
Tue Mar 31 03:53:05 EDT 2009

That works, but I guess a case statement would be nicer:
case compare r 0 of
  LT -> LEFT

This uses the compare function, which results in a value of the Ordering
datatype, which consists of the constructors LT, EQ and GT.

Peter Hickman wrote:
> I've just written this piece of code
>     if r < 0
>     then LEFT
>     else
>         if r > 0
>         then RIGHT
>         else STRAIGHT
> which works just fine but it does look rather clunky (as it would in any
> language I suppose). Is there a Haskell idiom for this type of code?
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