Are you looking for something like Streams [1]?
They're infinite sequences, defined like this:
data Stream a = Cons a (Stream a)
They can obviously never be empty (unless you see bottom (undefined) as empty).
- Tom
[1] http://hackage.haskell.org/cgi-bin/hackage-scripts/package/Stream
On Thu, Jun 4, 2009 at 11:53 PM, GüŸnther Schmidt
Hi,
I need to design a container data structure that by design cannot be empty and can hold n elements. Something like a non-empty list.
I started with:
data Container a = Single a | Many a [a]
but the problem above is that the data structure would allow to construct a Many 5 [] :: Container Int.
I can't figure out how to get this right. :(
Please help.
Günther
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