peraino@gmuvax2.gmu.edu (Bob Peraino) (01/26/91)
In article <25590090@hpcvra.cv.hp.com.> billw@hpcvra.cv.hp.com. (William C Wicke s) writes: >I hate to complain about an otherwise nice program, but... > >Using CLEAR is a nasty thing to do to an unsuspecting 48. IMHO, any >program should be able to clean up after itself without trashing stack >objects that it didn't put there. And I shouldn't have to read a >program's listing to figure out how to defend against its side >effects. > >Bill Wickes >HP Corvallis I wholeheartedly agree! The 48 is a VERY modular machine. Code should ALWAYS leave the machine in the state it was before entering the code. This goes beyond the stack; don't forget flags and variables. peraino@gmuvax.gmu.edu
akcs.kevin@hpcvbbs.UUCP (Kevin Jessup) (01/27/91)
I agree!! I wish more HP48SX programmers would use the PRESERVE program that save flags, runs the application and then restores the flags. I usually end up modifying the main routine of other peoples programs to incorporate this function. The program is described on page 555 od the 48SX (Rev A) manuals. PRESERVE \<< RCLF \\-> f \<< EVAL f STOF \>> \>> Preserve will save the flags, evaluate the object on LEVEL 1 and restore the flags.