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deriving in Clean
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Stephan Haugh
Mar 1, 2003, 5:14:16 PM3/1/03
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Sorry this is a real newbie question. I am sure it is the Clean book,
only I can't seem to find it. Searched all over the web too.
only I can't seem to find it. Searched all over the web too.
I have declared a new datatype in clean
::DataType = BoolData | StringData | IntData
Now, how would I compare two instances of this new type? In Haskell I
would write it like this:
> data DataType
> = BoolData | StringData | IntData
> deriving (Eq, Read, Show)
and away I go. I can now use == to compare two instances of this type.
So I wonder how to achieve that in Clean. All I managed so far is
defining instances of (==) for this new type. That is a bit
long-winded. Any help appreciated.
Cheers, Stephan
Fabien Todescato
Mar 2, 2003, 1:37:00 PM3/2/03
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Hi Stephan,
AFAIK, as of version 2.0.2, Clean supports generic programming that you may want
to use to support automatic derivation of ==.
Best regards, Fabien
Steffen Haugk
Mar 6, 2003, 8:05:55 AM3/6/03
to
Thank you. I have seen chapter 7 in the new Clean report. My
conclusion is that it is nowhere near as simple as it is in Haskell.
Thanks,
Steffen
conclusion is that it is nowhere near as simple as it is in Haskell.
Thanks,
Steffen
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