Hi Rodrigo,
> Just one more question, I didn't find any example describing how to get the
> text information of a XML element in the picklers tutorial. So, if the use
> case
> element is described as follwing:
> ...
here is a complete example for your use case.
Take the following XML data in file "uc.xml"
------------------------
<useCaseModel name="firstUseCaseModel">
<useCase>
<id>UC_01</id>
<name>Opening ...</name>
<description>This use case describes how...</description>
</useCase>
</useCaseModel>
------------------------
and the following picker and test
------------------------
module Main
where
import Text.XML.HXT.Arrow
type Id = String
type Name = String
type Description = String
data UseCaseModel
= UCM Name [UseCase]
deriving (Show)
data UseCase
= UseCase Id Name Description
deriving (Show)
instance XmlPickler UseCase where
xpickle = xpUseCase
xpUseCaseModel :: PU UseCaseModel
xpUseCaseModel =
xpElem "useCaseModel" $
xpWrap ( uncurry UCM
, \ (UCM n ucs) -> (n, ucs) ) $
xpPair ( xpAttr "name" xpText )
( xpList xpUseCase )
xpUseCase :: PU UseCase
xpUseCase =
xpElem "useCase" $
xpWrap ( uncurry3 UseCase
, \ (UseCase i n d) -> (i, n, d) ) $
xpTriple (xpElem "id" xpText)
(xpElem "name" xpText)
(xpElem "description" xpText)
main :: IO ()
main
= do
runX ( xunpickleDocument xpUseCaseModel
[ (a_validate,v_0)
, (a_trace, v_1)
, (a_remove_whitespace,v_1) -- !!!!!!!!!! throw away
whitespace
, (a_preserve_comment, v_0) -- !!!!!!!!!! throw away
comments
] "uc.xml"
>>>
processUseCaseModel
>>>
xpickleDocument xpUseCaseModel
[ (a_indent, v_1)
] "new-uc.xml"
)
return ()
-- the dummy for processing the unpickled data
processUseCaseModel :: IOSArrow UseCaseModel UseCaseModel
processUseCaseModel
= arrIO ( \ x -> do {print x ; return x})
-----------------------
This program will print the internal haskell value and
writes the data to "new-uc.xml"
Cheers
Uwe
--
Uwe Schmidt
Web: http://www.fh-wedel.de/~si/
_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe
