On Sun, 2006-08-13 at 20:36 +0200, Marc Weber wrote:
Is there somethinig corresponding to Num concering lists?
I mean there is + - /.. defined. + - are not type specific (Int, Double) neither is : [1,2] notation to Elements.. But what about different implementatins of lists? (linked lists? hash lists? array with index?
In other words: why not overload (:) ?
It might be nice to be able to use (:) to deconstruct other list like representations however the other list representations cannot efficiently support construction with (:). For example for the array-with-an-index representation it is an O(n) operation.
Then it would be possible to use "blah" for fast packed strings, too
An easier way of doing that might be to define literal strings to desugar into a function application much like numeric literals desugar into applications of fromIntegral. At the moment we can at least get the performance benefit of not converting via a list representation using GHC rules. So if you write: pack "blah" it gets transformed into: packAddr "blah"# where that literal string is just the address of a constant C string. Duncan