[Haskell-cafe] Why does Haskell have the if-then-else syntax?

[Fritz Ruehr]

On Jul 26, 2006, at 6:44 PM, Sebastian Sylvan wrote:

> For example ...
>
> if :: Bool -> a -> a -> a
> if True t _ = t
> if False _ e = e
>
> -- example usage
> myAbs x = if (x < 0) (negate x) x

I suppose there might also be a case for flipping the arguments about 
like this:

     if :: a -> a -> Bool -> a
     if t _ True = t
     if _ e False = e

This way it would follow foldr more closely, in recognition that the 
conditional is essentially the fold/cata/eliminator/... for booleans.

But argument order is a pretty trivial thing, and I think the committee 
made the right choice with if-then-else as a language construct.

   --  Fritz