# File lib/arrayfields.rb, line 42
      def pos f
        return @fieldpos[f] if @fieldpos.has_key? f 
        f = f.to_s
        return @fieldpos[f] if @fieldpos.has_key? f 
        f = f.intern
        return @fieldpos[f] if @fieldpos.has_key? f 
        nil
      end