At 13:18 97/05/16, [EMAIL PROTECTED] wrote:
I'm the one responsible for adding the Monad laws to the Haskell
report [library] - so perhaps I should explain why I wanted to add them.
I had a look at these library monad laws, and, actually, it turns out
that the
liftM :: (Monad m) = (a
I'm the one responsible for adding the Monad laws to the Haskell
report - so perhaps I should explain why I wanted to add them.
The main reason I wanted to add them was so that I could (informally)
appeal to them when documenting code or optimising code. For example,
the Monad library
Philip Wadler wrote:
| 1. zero = k = zero
| 2. m = \x - zero= zero
| 3. (m ++ n) = k = m = k ++ n = k
| 4. m = \x - k x ++ h x = m = k ++ n = k.
|
| But the fourth law does not hold for lists, and the second law does
| not hold if we consider
