[Haskell] recursive definitions in Haskell (inductive and coinductive)

Norman Ramsey nr at cs.tufts.edu
Tue Feb 2 20:41:52 EST 2010

 > AFAIK, the normal understanding is that recursive types
 > are the least fixed points of endofunctors on the category of CPOs,
 > and it is the CPO property that least upper bounds of chains exist
 > that forces the existence of infinite lists.

But ML has CPOs and infinite chains too!  The situation is simpler
because the only *interesting* infinite ascending chains are in
function domains.

To paraphrase, is what you're saying that the definition of a Haskell
type is the smallest fixed point that contains the bottom element
(divergent computation) as a member?


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