[Haskell-cafe] Infinite grid

[Martijn van Steenbergen]

Hello,

I would like to construct an infinite two-dimensional grid of nodes, 
where a node looks like this:

> data Node = Node
>   { north :: Node
>   , east  :: Node
>   , south :: Node
>   , west  :: Node
>   }

in such a way that for every node n in the grid it doesn't matter how I 
travel to n, I always end up in the same memory location for that node.

I suspect another way of saying that is that

> let f = f . north . east . south . west in f origin

should run in constant space. I hope this makes the problem clear. :-)

How do I do this?

Thanks in advance,

Martijn.