[Haskell-cafe] Non Empty List?

GüŸnther Schmidt gue.schmidt at web.de
Thu Jun 4 17:53:06 EDT 2009


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.


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