Well, the version without USING (not USAGE, of course), was not obvious at all to me until a few days ago, after 20 years of seeing it and not understanding it... Now that I understand it, though, I do find it quite readable. And I think I agree with your personal rule.
Thanks! Frank -----Original Message----- From: IBM Mainframe Assembler List <[email protected]> On Behalf Of Charles Mills Sent: Wednesday, March 29, 2023 9:22 PM To: [email protected] Subject: [EXTERNAL] Re: alternative to USAGE statement? An alternative to the USING statement? The only difference is in the source code. The executable machine code is the same. The question is what is clearest to you? My personal rule is that for one or perhaps two references, AFLENG-DFHACB(,R12) is simpler and cleaner, and for more references than that, you should definitely code a USING/DROP pair. But every coder's mileage may vary. The latter I would call USING/DROP; I don't have a name for the former. Perhaps "computed offset"? Charles -----Original Message----- From: IBM Mainframe Assembler List [mailto:[email protected]] On Behalf Of Swarbrick, Frank Sent: Wednesday, March 29, 2023 5:16 PM To: [email protected] Subject: alternative to USAGE statement? 20 year amateur assembler programmer here. Sometimes I see macro expansions (and just open code) with code like the following. L 12,X'14'(,12) AH 12,AFLENG-DFHAFCB(,12) L 12,AFPFXLEN+AFTKTCB-AFTSTART(,12) LLGT 12,UKTCB_ACTIVE_TASK-DFHUKTCB(,12) LLGT 12,UTATCAA-DFHUTASN(,12) Is that code equal to this? L 12,X'14'(,12) USING DFHAFCB,12 AH 12,AFLENG USING AFTSTART,12 L 12,AFPFXLEN+AFTKTCB USING DFHUKTCB LLGT 12,UKTCB_ACTIVE_TASK USING DFHUTASN LLGT 12,UTATCAA(,12) What is the "name" of this usage? The information contained in this electronic communication and any document attached hereto or transmitted herewith is confidential and intended for the exclusive use of the individual or entity named above. If the reader of this message is not the intended recipient or the employee or agent responsible for delivering it to the intended recipient, you are hereby notified that any examination, use, dissemination, distribution or copying of this communication or any part thereof is strictly prohibited. If you have received this communication in error, please immediately notify the sender by reply e-mail and destroy this communication. Thank you. The information contained in this electronic communication and any document attached hereto or transmitted herewith is confidential and intended for the exclusive use of the individual or entity named above. If the reader of this message is not the intended recipient or the employee or agent responsible for delivering it to the intended recipient, you are hereby notified that any examination, use, dissemination, distribution or copying of this communication or any part thereof is strictly prohibited. If you have received this communication in error, please immediately notify the sender by reply e-mail and destroy this communication. Thank you.
