The most natural seeming thing is one permutation you don't mention:
do x <- if cond then Just $ textInputField ...
else return Nothing
...
... submit ... -- perhaps: maybe (return ()) submit x
-- or submit (fromMaybe <something> x)
. Does that do what you want?
mike
John Goerzen
Thanks for everyone that's helped me out with my Wash questions. I have one more.
I have a textInputField that I only want to display on a form in certain cituations. I can't figure out how to make this work. For instance:
... do if cond then x <- textInputField ... else () ... submit ...
Well, two problems there... first, the scope of the x doesn't reach to the submit. Second, there's a type issue. So I thought maybe I could figure out something like this:
... do x <- if cond then textInputField ... else ()
still stuck with the typing problem.
So I thought maybe something like this...
... do let x = if cond then Just $ textInputField ... else Nothing
Though I suspect this won't work either, since the textInputField won't actually be processed at the right place in the program.
I then thought maybe I could kludge by this with a hidden field, but I can't find one of those, either.
Ideas, anyone?
Thanks, John
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