Re: [Haskell-cafe] Why is Bool no instance of Num and Bits?

Neil Mitchell wrote:

I didn't at first, then I remembered:

1 + True = fromInteger 1 + True

And if we have Num for Bool, it type checks.

Does that also mean that you could write: if 3 - 4 then ... else ... (= if (fromInteger 3 :: Bool) - (fromInteger 4 :: Bool) then ... else ...) or perhaps (not sure if type defaulting stretches to this): if 1 then ... else ... (= if (fromInteger 1 :: Bool) then ... else ...) If you change fromInteger in Num Bool to be fromInteger x = x /= 0, then we could all start writing nasty C-like if-expressions... Thanks, Neil.