On 8/14/07, Jeff Polakow
One general intuition about monads is that they represent computations rather than simple (already computed) values:
x :: Int -- x is an Int x :: Monad m => m Int -- x is a computation of an Int
What's a "computation"? It seems to me that in a lazy language, x::Int represents a computation of an int, not an "already computed" value. x::[Int] is a computation that returns multiple values. x::(Int,Int) is a computation that returns a pair of values. x::() is a computation that returns nothing. x::Map a b is a computation that gives a way to associate values of type a with values of type b. Some of these are monads, some are not. What's the difference between them? Why are you calling certain values "computations"? -- Dan