Matrix pavings and Laurent operators

A tape measure equipped with a stopper which stops a rule when the rule drawn into a case by an elastic force is pulled out from the case is disclosed. In this tape measure, by a button-pushing operation, a pressing piece of the stopper is caused to slide in the direction vertical to the rule, and the pressing piece is held and maintained in the state where the pressing piece has pressing contact with the rule or in the state where the pressing piece is separated from the rule.