[Haskell-cafe] Non Empty List?

[Jake McArthur]

GüŸnther Schmidt wrote:
> 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 think you meant to do either

     data Container a = Single a | Many a (Container a)

or

     data Container a = Container a [a]

- Jake