# File rexml/xpath_parser.rb, line 39
    def initialize( )
      @parser = REXML::Parsers::XPathParser.new
      @namespaces = nil
      @variables = {}
    end

# File rexml/xpath_parser.rb, line 76
    def []=( variable_name, value )
      @variables[ variable_name ] = value
    end

# File rexml/xpath_parser.rb, line 85
    def first( path_stack, node )
      #puts "#{depth}) Entering match( #{path.inspect}, #{tree.inspect} )"
      return nil if path.size == 0

      case path[0]
      when :document
        # do nothing 
        return first( path[1..-1], node )
      when :child
        for c in node.children
          #puts "#{depth}) CHILD checking #{name(c)}"
          r = first( path[1..-1], c )
          #puts "#{depth}) RETURNING #{r.inspect}" if r
          return r if r
        end
      when :qname
        name = path[2]
        #puts "#{depth}) QNAME #{name(tree)} == #{name} (path => #{path.size})"
        if node.name == name
          #puts "#{depth}) RETURNING #{tree.inspect}" if path.size == 3
          return node if path.size == 3
          return first( path[3..-1], node )
        else
          return nil
        end
      when :descendant_or_self
        r = first( path[1..-1], node )
        return r if r
        for c in node.children
          r = first( path, c )
          return r if r
        end
      when :node
        return first( path[1..-1], node )
      when :any
        return first( path[1..-1], node )
      end
      return nil
    end

# File rexml/xpath_parser.rb, line 63
    def get_first path, nodeset
     #puts "#"*40
     path_stack = @parser.parse( path )
     #puts "PARSE: #{path} => #{path_stack.inspect}"
     #puts "PARSE: nodeset = #{nodeset.inspect}"
     first( path_stack, nodeset )
    end

# File rexml/xpath_parser.rb, line 126
    def match( path_stack, nodeset ) 
      #puts "MATCH: path_stack = #{path_stack.inspect}"
      #puts "MATCH: nodeset = #{nodeset.inspect}"
      r = expr( path_stack, nodeset )
      #puts "MAIN EXPR => #{r.inspect}"
      r
    end

# File rexml/xpath_parser.rb, line 45
    def namespaces=( namespaces={} )
      Functions::namespace_context = namespaces
      @namespaces = namespaces
    end

# File rexml/xpath_parser.rb, line 55
    def parse path, nodeset
     #puts "#"*40
     path_stack = @parser.parse( path )
     #puts "PARSE: #{path} => #{path_stack.inspect}"
     #puts "PARSE: nodeset = #{nodeset.inspect}"
     match( path_stack, nodeset )
    end

# File rexml/xpath_parser.rb, line 71
    def predicate path, nodeset
      path_stack = @parser.parse( path )
      expr( path_stack, nodeset )
    end

# File rexml/xpath_parser.rb, line 50
    def variables=( vars={} )
      Functions::variables = vars
      @variables = vars
    end