I just found myself writing a function that looked like this:
isSubsumedByWith :: TBox c -> c -> c -> Bool isSubsumedByWith [] c d = isALSubsumedBy c d isSubsumedByWith _ _ _ = error "TBox reasoning not supported for AL"
and immediately noticed that I might also write this:
isSubsumedByWith :: TBox c -> c -> c -> Bool isSubsumedByWith [] = isALSubsumedBy isSubsumedByWith _ = error "TBox reasoning not supported for AL"
which led me to thinking about the difference between these two functions (I reason there must be a difference, because the call of 'error' is required to fulfil (terminology?) values of different types). I think it is this: Suppose I evaluate an expression: let s = isSubsumedByWith [foo] in seq s e then I think the first case will return a legitimate function, albeit one that returns error when it is applied, and the second will cause an error to be returned immediately. Am I right? Is this all? #g ------------ Graham Klyne For email: http://www.ninebynine.org/#Contact