On Tue, Apr 29, 2008 at 8:54 AM, rodrigo.bonifacio wrote:

Hi all,

I have the following data types:

type Id = String type Action = String type State = String type Response = String

data Scenario = Scenario Description [Step] data Step = Step Id Scenario Action State Response

So, there is a mutual recursion between Scenario and Step. Now, consider the following function:

xmlScenario2Scenario :: XmlScenario -> Scenario xmlScenario2Scenario (XmlScenario description steps) = Scenario description [xmlStep2Step x | x <-steps]

How can I send "scenario" as an argument for xmlStep2Step?

Like this: let scenario = Scenario description [xmlStep2Step scenario x | x <- steps] in scenario

I've tried let and where but I get in a loop.

So it sounds like you already tried what I suggested. If you get in a loop, then whatever you are doing is too strict to handle this kind of self-reference. But it's hard to give suggestions without seeing more of the code. Luke