> Sorry,
>
> I've just worked it out.
>
> PortNumber is an instance of the class Enum
> so we can use
>
> toEnum :: Int -> a
It's also an instance of the Integral class, which means you can just
write integral constants of type PortNumber. eg. (80 :: PortNumber) is
valid. Also, the univers
Sorry,
I've just worked it out.
PortNumber is an instance of the class Enum
so we can use
toEnum :: Int -> a
Tom
On Tue, 3 Jun 2003 05:25 pm, Thomas L. Bevan wrote:
> Hi,
>
> How can I take some input and convert this into a
> PortID ?
> I don't quite understand why the constructor
> PortNumb
Hi,
How can I take some input and convert this into a
PortID ?
I don't quite understand why the constructor
PortNumber doesn't have the signature
PortID = PortNumber Int | ...
Instead it is
PortID = PortNumber PortNumber
where PortNumber is not a member of the Read class.
Tom
It would probably be helpful if you were to post the code you have and
explain what part isn't working. There's a function:
readFile :: FilePath -> IO String
(FilePath is just a String)
which reads a file. This should be what you need to solve this
exercise...
- Hal
--
Hal Daume III
> However one of the commands is: read filename
> i.e. read a file and display it.
> I do not succeed in implementing this.
http://www.haskell.org/hawiki/ThatAnnoyingIoType
http://www.haskell.org/hawiki/UsingIo
are your friends.
--KW 8-)
--
Keith Wansbrough <[EMAIL PROTECTED]>
http://www.cl.c
