On Thu, Apr 19, 2007 at 02:47:30AM +0100, Neil Mitchell wrote:
Hi,
I've been wondering what is essential to Haskell and what isn't. Not from a point of view of what could be removed from the language, but what could be removed from a Core language.
Given the features of higher-order, laziness and data types:
Laziness can be converted to higher-order functions
Is this a pure language? If so you have to lose asymptotic performance in some cases, In "More haste, less speed: lazy versus eager evaluation" by Richard Bird, Geraint Jones and Oege De Moor there's an example of a function that can be implemented in linear time in a lazy language but requires O(n log n) time in a strict pure language. It doesn't matter if you just want to reason about results, and on the other hand for an intermediate language I suppose you might prefer to add state and explicitly manipulate the thunking. Brandon