[Haskell-cafe] ????Pattern match(es) are overlapped???

S. Alexander Jacobson alex at alexjacobson.com
Mon Mar 22 14:14:56 EST 2004


I actually ended up using a lookup list e.g.

   handlers=[(getMethod,doGet),(putMethod,doPut)]

which has the convenience of being able to put a
501 "Not Implemented" in an obvious place.

I'll post the code shortly.  My goal is to form
the core of a generically useful HTTP
haskell server library.

-Alex-


On Mon, 22 Mar 2004, Ketil Malde wrote:

> "Arjan van IJzendoorn" <afie at cs.uu.nl> writes:
>
> >>    newtype Method = Method String
> >>    getMethod = Method "GET"
> >>    putMethod = Method "PUT"
> >>    doMeth getMethod = ...
> >>    doMeth putMethod = ...
>
> > You will have to write:
> >
> > doMeth (Method "GET") = ...
> > doMeth (Method "PUT") = ...
>
> Or (I assume, haven't tested) if you insist on renaming the methods:
>
>   doMeth m | m == getMethod = ...
>            | m == putMethod = ...
>
> (or using a case statement, of course)
>
> -kzm
> --
> If I haven't seen further, it is by standing in the footprints of giants
>

_________________________________________________________________
S. Alexander Jacobson                  mailto:me at alexjacobson.com
tel:917-770-6565                       http://alexjacobson.com


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