Recursion vs Combinators.

John Carter — 2001-12-11 03:21:27

I'm in deep thought mode about recursion vs combinators.



The fact that you can elimanate recursion is a deeply fascinating thing in

itself, but beyond that fascination why should one do it?



ie. What does it give you?



Is it easier to prove things about a recursionless program?



A scan of Manfred's site again didn't reveal any obvious benefits, am I

missing something?



John Carter                             Phone : (64)(3) 358 6639

Tait Electronics                        Fax   : (64)(3) 359 4632

PO Box 1645 Christchurch                Email : john.carter@...

New Zealand



Zeitgeist shutting down for corrective maintenance, please log off.

Louis Madon — 2001-12-11 21:56:58

On Tuesday, December 11, 2001, at 01:21  PM, John Carter wrote:



 > I'm in deep thought mode about recursion vs combinators.

>

> The fact that you can elimanate recursion is a deeply fascinating thing 

> in

> itself, but beyond that fascination why should one do it?

>

> ie. What does it give you?

>

> Is it easier to prove things about a recursionless program?

>

> A scan of Manfred's site again didn't reveal any obvious benefits, am I

> missing something?



 
I don't think Manfred discusses the pros and cons at all.  It is an 

interesting question though, I only have a _hunch_ that it would be 

better, but I don't think anyone has seriously programmed that way to 

know for sure.



I prefer to avoid redundancy in language design and right now having 

both recursion combinators and recursive definitions in Joy does seem 

redundant.



Until there's been more theoretical and practical experience with 

recursion combinators (especially with respect to mutual recursion) I 

don't think your question can be properly answered.



In the meantime, my answer would be "Why not eliminate recursive 

definitions?"



Louis.





[Non-text portions of this message have been removed]