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diff --git a/src/Text/Pandoc/XML/Light/Proc.hs b/src/Text/Pandoc/XML/Light/Proc.hs
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+{-# LANGUAGE FlexibleInstances #-}
+{- |
+   Module      : Text.Pandoc.XML.Light.Proc
+   Copyright   : Copyright (C) 2007 Galois, Inc., 2021 John MacFarlane
+   License     : GNU GPL, version 2 or above
+
+   Maintainer  : John MacFarlane <jgm@berkeley.edu>
+   Stability   : alpha
+   Portability : portable
+
+   This code is taken from xml-light, released under the BSD3 license.
+-}
+module Text.Pandoc.XML.Light.Proc
+  ( 
+    -- * Replacement for xml-light's Text.XML.Proc
+    strContent
+  , onlyElems
+  , elChildren
+  , onlyText
+  , findChildren
+  , filterChildren
+  , filterChildrenName
+  , findChild
+  , filterChild
+  , filterChildName
+  , findElement
+  , filterElement
+  , filterElementName
+  , findElements
+  , filterElements
+  , filterElementsName
+  , findAttr
+  , lookupAttr
+  , lookupAttrBy
+  , findAttrBy
+  ) where
+
+import Data.Text (Text)
+import Data.Maybe (listToMaybe)
+import Data.List(find)
+import Text.Pandoc.XML.Light.Types
+
+--
+-- copied from xml-light Text.XML.Proc
+--
+
+-- | Get the text value of an XML element.  This function
+-- ignores non-text elements, and concatenates all text elements.
+strContent         :: Element -> Text
+strContent          = mconcat . map cdData . onlyText . elContent
+
+-- | 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 Text
+findAttr x e       = lookupAttr x (elAttribs e)
+
+-- | Lookup attribute name from list.
+lookupAttr        :: QName -> [Attr] -> Maybe Text
+lookupAttr x       = lookupAttrBy (x ==)
+
+-- | Lookup the first attribute whose name satisfies the given predicate.
+lookupAttrBy       :: (QName -> Bool) -> [Attr] -> Maybe Text
+lookupAttrBy p as   = attrVal `fmap` find (p . attrKey) as
+
+-- | Lookup the value of the first attribute whose name
+-- satisfies the given predicate.
+findAttrBy         :: (QName -> Bool) -> Element -> Maybe Text
+findAttrBy p e      = lookupAttrBy p (elAttribs e)
+
+