On Thu, 12 Jun 2003, Wolfgang Jeltsch wrote:

On Thursday, 2003-06-12, 18:01, CEST, Filip wrote:

...

Hi,

I wrote something like "let t = try (hGetLine h1)" and I would like to check is it EOFError or not. How can I do this ??

Thanks

Hello,

the above code assigns the I/O action try (hGetLine h1) to t. I suppose you want to assign the result of this action to t. If this is the case, you have to write t <- try (hGetLine h1). You can then examine t as in the following example: t <- try (hGetLine h1) case t of Left error | isEOFError error -> do <EOF handling> Right result -> do <normal continuation>

Beware: The above causes pattern match failure if a true error (other than end of file) occurs. You probably want something like: case t of Left error | isEOFError error -> do <EOF handling> | otherwise -> do <error handling> Right result -> do <normal continuation>

A better way might be to use catch which is exported from the Prelude.

Dean