def foreign_invoke(gram, name, args=nil)
      ForeignInvokeRule.new gram, name.to_s, args
    end
def foreign_invoke(gram, name, args=nil)
      ForeignInvokeRule.new gram, name.to_s, args
    end
Invoke a rule defined on a foreign grammar
 == Parameters:
 gram::
   The name of the grammar that the rule will be reference from
 name::
   The name of the rule that will be invoked
 args::
   Any arguements that should be passed to the rule
 == Returns:
   A new ForeignInvokeRule