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+--------------------------------------------------------------------
+-- |
+-- Module    : Text.XML.Light.Proc
+-- Copyright : (c) Galois, Inc. 2007
+-- License   : BSD3
+--
+-- Maintainer: Iavor S. Diatchki <diatchki@galois.com>
+-- Stability : provisional
+-- Portability:
+--
+--------------------------------------------------------------------
+
+
+module Text.XML.Light.Proc where
+
+import Text.XML.Light.Types
+
+import Data.Maybe(listToMaybe)
+import Data.List(find)
+
+-- | Get the text value of an XML element.  This function
+-- ignores non-text elements, and concatenates all text elements.
+strContent         :: Element -> String
+strContent e        = concatMap cdData $ onlyText $ elContent e
+
+-- | Select only the elements from a list of XML content.
+onlyElems          :: [Content] -> [Element]
+onlyElems xs        = [ x | Elem x <- xs ]
+
+-- | Select only the elements from a parent.
+elChildren         :: Element -> [Element]
+elChildren e        = [ x | Elem x <- elContent e ]
+
+-- | Select only the text from a list of XML content.
+onlyText           :: [Content] -> [CData]
+onlyText xs         = [ x | Text x <- xs ]
+
+-- | Find all immediate children with the given name.
+findChildren       :: QName -> Element -> [Element]
+findChildren q e    = filterChildren ((q ==) . elName) e
+
+-- | Filter all immediate children wrt a given predicate.
+filterChildren       :: (Element -> Bool) -> Element -> [Element]
+filterChildren p e    = filter p (onlyElems (elContent e))
+
+
+-- | Filter all immediate children wrt a given predicate over their names.
+filterChildrenName      :: (QName -> Bool) -> Element -> [Element]
+filterChildrenName p e   = filter (p.elName) (onlyElems (elContent e))
+
+
+-- | Find an immediate child with the given name.
+findChild          :: QName -> Element -> Maybe Element
+findChild q e       = listToMaybe (findChildren q e)
+
+-- | Find an immediate child with the given name.
+filterChild          :: (Element -> Bool) -> Element -> Maybe Element
+filterChild p e       = listToMaybe (filterChildren p e)
+
+-- | Find an immediate child with name matching a predicate.
+filterChildName      :: (QName -> Bool) -> Element -> Maybe Element
+filterChildName p e   = listToMaybe (filterChildrenName p e)
+
+-- | Find the left-most occurrence of an element matching given name.
+findElement        :: QName -> Element -> Maybe Element
+findElement q e     = listToMaybe (findElements q e)
+
+-- | Filter the left-most occurrence of an element wrt. given predicate.
+filterElement        :: (Element -> Bool) -> Element -> Maybe Element
+filterElement p e     = listToMaybe (filterElements p e)
+
+-- | Filter the left-most occurrence of an element wrt. given predicate.
+filterElementName     :: (QName -> Bool) -> Element -> Maybe Element
+filterElementName p e  = listToMaybe (filterElementsName p e)
+
+-- | Find all non-nested occurances of an element.
+-- (i.e., once we have found an element, we do not search
+-- for more occurances among the element's children).
+findElements       :: QName -> Element -> [Element]
+findElements qn e = filterElementsName (qn==) e
+
+-- | Find all non-nested occurrences of an element wrt. given predicate.
+-- (i.e., once we have found an element, we do not search
+-- for more occurances among the element's children).
+filterElements       :: (Element -> Bool) -> Element -> [Element]
+filterElements p e
+ | p e        = [e]
+ | otherwise  = concatMap (filterElements p) $ onlyElems $ elContent e
+
+-- | Find all non-nested occurences of an element wrt a predicate over element names.
+-- (i.e., once we have found an element, we do not search
+-- for more occurances among the element's children).
+filterElementsName       :: (QName -> Bool) -> Element -> [Element]
+filterElementsName p e = filterElements (p.elName) e
+
+-- | Lookup the value of an attribute.
+findAttr           :: QName -> Element -> Maybe String
+findAttr x e        = attrVal `fmap` find ((x ==) . attrKey) (elAttribs e)
+
+-- | Lookup attribute name from list.
+lookupAttr           :: QName -> [Attr] -> Maybe String
+lookupAttr x as        = attrVal `fmap` find ((x ==) . attrKey) as
+