   exports.extract = extract
   exports.Description = Description
   exports.State = State
-  exports.Mapper = Mapper
+  exports.Context = Context
   exports.ElementData = ElementData
   exports.contexts = contexts
 

  class State
    constructor: (@base, @profile, resolveURI) ->
      @resolveURI = resolveURI
      @mapper = new Mapper(null, contexts[@profile])
      @lang = null

      @lists = {}

        return expr
      if term.slice(0, 2) is "//"
        return expr
      ns = @prefixes[pfx]
      if ns
        return ns + term
      return expr
