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Rick: The 1 DOWEQ 1 construct is not really the logic of the loop. The logic of the loop is really continue the loop until you press F3 or F12 to exit. Instead of using *INKC and *INKL we normally define an INFDS and check the AID byte. (Remember S/3 CCP and RPG II?) The named constants could be copied using a /COPY. We would also use SELEC/WHEN instead of a series of IF/ENDIFs. We would probably code the same routine as follows: FSCREEN CF E WORKSTN KINKDS SCRNDS IDsname....NODsExt-file++............PFromTo++DField......... ISCRNDS DS * ATTENTION INDICATOR I 369 369 $$FKEY I..............Constant++++++++++++++C.........Const+........ * NAMED CONSTANTS I X'31' C ##F01 I X'34' C ##F04 I X'3C' C ##F12 C F1DISP BEGSR C EXSR F1INZ (any pre-screen processing) C MOVE 'N' #EXIT1 C #EXIT1 DOWNE 'Y' (loop continues until , C EXFMT FMT1 exit set) (#EXIT1 DOWEQ 'N' would also be valid but I tend to think in the negative.) C SELEC C $$FKEY WHEQ ##F03 (If F3 or F12 is C $$FKEY OREQ ##F12 pressed, set loop exit) C MOVE 'Y' #EXIT1 C $$FKEY WHEQ ##F04 C EXSR @@INQ1 (prompt/lookup inquiry calls) C OTHER C EXSR @@EDT1 (input field editing) C $ERROR IFNE 'Y' C EXSR @@UPD1 (file update) C EXSR @@INZ1 C ENDIF (Again, $ERROR IFEQ 'N' could also be used.) C ENDSL C ENDDO C ENDSR For the edit routine, instead of coding a DO at the start of the subroutine and an ENDDO several pages later, we always reverse the subroutine name to form the ENDSR tag. An @@xxxx ALWAYS represents a subroutine BEGSR and a xxxx@@ ALWAYS represents the end of the subroutine. Yes, the GOTO drives structured purists wild but an exit to the end of a routine is structured code and we ALWAYS code this the same way in every program. This is the only time we use a GOTO and will do so until we get a LEAVE type op code to exit a subroutine. C @@EDT1 BEGSR C MOVE 'N' $ERROR C KEY1 CHAIN FILE1 90 C *IN90 IFEQ *ON C..... insert your error messaging code of choice C MOVE 'Y' $ERROR C GOTO EDT1@@ C END C KEY2 CHAIN FILE2 90 C *IN90 IFEQ *ON C..... insert your error messaging code of choice C MOVE 'Y' $ERROR C GOTO EDIT@@ C END etc.... C EDIT@@ ENDSR If I am on the second edit, I can F EDIT@@ 18 or F ENDSR to easily go to the end of the subroutine in SEU. We do use ITER and LEAVE in DO, DOW, and DOU loops where appropriate. I anxiously await (look forward to?) the condemnations for using a GOTO. Be nice - remember no flames! Rick wrote: >Since were on the subject, I would like some opinions on a coding >technique that I've been using for several years now. I use the LEAVE >and ITER opcodes extensively as a sortof GOTO replacement (ooh, maybe >that isn't such a good thing to compare it to..... > >I like it (obviously) and I think it makes things a lot kinder on the >eyes. > >Here are a couple of examples: (doesn't line up, spaces added between >opcode and factor 2 to make it more readable) > >for screen processing subroutines: > >C F1DISP BEGSR > >C EXSR F1INZ (any pre-screen processing) > >C 1 DOWEQ 1 (obvious never-ending loop, >C EXFMT FMT1 requires LEAVE to exit) > >C *INKC IFEQ *ON (leave loop if F3 or F12 is >C *INKL OREQ *ON pressed) >C LEAVE >C END > >C *INKD IFEQ *ON >C EXSR F1PRMT (prompt/lookup inquiry calls) >C ITER (return to screen) >C END > >C EXSR F1EDIT (input field editing) >C $ERROR IFEQ *ON >C ITER >C END > >C EXSR F1UPDT (file update) >C EXSR F1INZ >C ITER >C ENDDO > >C ENDSR > >and the edit routine: > >C F1EDIT BEGSR > >C MOVE *OFF $ERROR > >C DO > >C KEY1 CHAIN FILE1 90 >C *IN90 IFEQ *ON >C..... insert your error messaging code of choice >C MOVE *ON $ERROR >C LEAVE >C END > >C KEY2 CHAIN FILE2 90 >C *IN90 IFEQ *ON >C..... insert your error messaging code of choice >C MOVE *ON $ERROR >C LEAVE >C END > >etc.... > >C ENDDO > >C ENDSR > >These techniques cut down on the nesting levels, and the code is very >re-usable. > >Comments? Does anyone else use the leave and iter opcodes as much? > >Is this readable to someone not used to seeing things done this way? > >Thanks, > >Rick >* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * >* This is the Midrange System Mailing List! To submit a new message, * >* send your mail to "MIDRANGE-L@midrange.com". To unsubscribe from * >* this list send email to MAJORDOMO@midrange.com and specify * >* 'unsubscribe MIDRANGE-L' in the body of your message. Questions * >* should be directed to the list owner / operator: david@midrange.com * >* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * >uucp > > Charlie Massoglia, Massoglia Technical Consulting, Inc. PO Box 1065, Okemos, MI 48854, USA 517-676-9700 Fax: 517-676-1006 EMAIL: cmassoglia@voyager.net * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * This is the Midrange System Mailing List! To submit a new message, * * send your mail to "MIDRANGE-L@midrange.com". To unsubscribe from * * this list send email to MAJORDOMO@midrange.com and specify * * 'unsubscribe MIDRANGE-L' in the body of your message. Questions * * should be directed to the list owner / operator: david@midrange.com * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
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