[Haskell-cafe] Re: Functional progr., infinity, and the Universe

[Paul Hudak]

Stepan Golosunov wrote:
>>>>1:_|_ is certainly finite.
>>>
>>>And what is length _|_ ?
>>
>>_|_, of course!! :-)
>>
>>The point being, length is well-defined only for total lists; it is 
>>undefined for partial lists.  But this doesn't mean that a partial list 
>>isn't finite.
> 
> What is "finite list" then?
> Is ones = 1:ones also finite?

Hmmm... never tried to write all this down in one place before, but I 
think this covers all cases:

A partial list is one that ends in _|_.
A total list is one that ends in [].
A finite list is either partial or total.
Any other list is infinite.

So "ones" is infinite.

-Paul