2008/5/1 Galchin, Vasili [EMAIL PROTECTED]:
Sorry .. my example was bad. I want to use x .. in then branch where
it occur ...
e.g.
bonzo :: Maybe Bozo - IO ()
bonzo maybe_bozo = do
case maybe_bozo of
Just (Bozo x) - x
_
data Bozo =
Bozo {
id :: Int
}
bonzo :: Maybe Bozo - IO ()
bonzo maybe_bozo = do
if maybe_bozo == (Just (Bozo x))
then
return ()
else
return ()
~
I want x to be a pattern that matches id ??
Kind regards, Vasili
Galchin, Vasili wrote:
data Bozo =
Bozo {
id :: Int
}
bonzo :: Maybe Bozo - IO ()
bonzo maybe_bozo = do
if maybe_bozo == (Just (Bozo x))
then
return ()
else
return ()
~
I want x to be a pattern that matches id ??
Try:
bonzo (Just
2008/5/2 Galchin, Vasili [EMAIL PROTECTED]:
data Bozo =
Bozo {
id :: Int
}
bonzo :: Maybe Bozo - IO ()
bonzo maybe_bozo = do
if maybe_bozo == (Just (Bozo x))
then
return ()
else
return ()
bonzo maybe_bozo =
case maybe_bozo of
Sorry .. my example was bad. I want to use x .. in then branch where it
occur ...
e.g.
bonzo :: Maybe Bozo - IO ()
bonzo maybe_bozo = do
case maybe_bozo of
Just (Bozo x) - x
_- .
??
Thanks, V.
On Thu,
Here is a simpler case of what I want to do ..
1) To function1 pass in (Maybe Int).
2) If Nothing then pass nullPtr to C function.
3) If Just 1, then pass a pointer to a 1 to teh same C function.
Thanks, Vasili
On Thu, May 1, 2008 at 8:18 PM, Galchin, Vasili [EMAIL PROTECTED] wrote:
Sorry
2008/5/1 Galchin, Vasili [EMAIL PROTECTED]:
Here is a simpler case of what I want to do ..
1) To function1 pass in (Maybe Int).
2) If Nothing then pass nullPtr to C function.
3) If Just 1, then pass a pointer to a 1 to teh same C function.
Check out Foreign.maybeWith.
