Resource Files

• exercise559.zip
• XML.lhs
  Solution Template
• XML.pdf
  Der Aufgabentext als PDF.

> module XML where > data XML > = Text (Maybe XML) Index String > |Element (Maybe XML) Index Name Attributes ChildNodes > type Name = String > type ChildNodes = [XML] > type Attribute = (Key,Value) > type Attributes = [Attribute] > type Key = String > type Value = String > type Index = Int > instance (Show XML) where > show (Text _ _ txt) = txt > show (Element _ _ name attrs cs) > = "<"++name++concatMap showAttr attrs++">" > ++concatMap show cs++"</"++name++">" > where > showAttr (k,v) = " "++k++"=\""++v++"\"" > instance (Eq XML) where > (Text _ i1 txt1) == (Text _ i2 txt2) = txt1 == txt2 > (Element _ i1 name1 attrs1 cs1) == (Element _ i2 name2 attrs2 cs2) > = name1==name2 && attrs1==attrs2 && cs1==cs2 > _ == y = False > mkElement :: Name -> Attributes -> [XML] -> XML > mkElement n as cs = r > where > r = Element Nothing (-1) n as (map (setParent r)(zip [0..] cs)) > setParent p (n, (Text _ _ txt) ) = Text (Just p) n txt > setParent p (n, (Element _ _ na as cs)) = r > where > r = Element (Just p) n na as (map (setParent r)(zip [0..] cs)) > mkText :: String -> XML > mkText = Text Nothing (-1) > type XPathAchsis = XML -> [XML] > self :: XPathAchsis > self n = [] > parent :: XPathAchsis > parent _ = [] > ancestor :: XPathAchsis > ancestor x = [] > ancestorOrSelf :: XPathAchsis > ancestorOrSelf _ = [] > child :: XPathAchsis > child _ = [] > descendant :: XPathAchsis > descendant x = [] > descendantOrSelf :: XPathAchsis > descendantOrSelf x = [] > followingSibbling :: XPathAchsis > followingSibbling _ = [] > precedingSibbling :: XPathAchsis > precedingSibbling _ = [] > following :: XPathAchsis > following xml = [ ] > preceding :: XPathAchsis > preceding xml = [ ]