# File kwartz.rb, line 3013
        def self.prior?(op1, op2)
            pr1 = @@priority[op1]
            pr2 = @@priority[op2]
            Kwartz::assert() unless pr1
            #Kwartz::assert() unless pr2
            pr2 = 0 if !pr2
            return nil if pr1 == pr2
            return pr1 < pr2
        end