>We were all very conscious of "economy in all things programming" in those days.
We? I've been programming since 1960, and I was never concerned with how much space the source code took. The important things were how quickly the code ran and how easy it was to maintain. There's economy and there's false economy. >A label would consume two lines of printout, Not unless you had it on an extraneous DS 0H, EQU *, or equivalent, and even then an extra line on the listing was no big deal. BTW, when I started 8-character labels would have sounded like Heaven; I was used to 5-character labels and even the big powerful 7090 only had 6-character labels. -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Assembler List <ASSEMBLER-LIST@listserv.uga.edu> on behalf of Charles Mills <charl...@mcn.org> Sent: Friday, August 3, 2018 11:12 AM To: ASSEMBLER-LIST@listserv.uga.edu Subject: Re: EQU * considered harmful We were all very conscious of "economy in all things programming" in those days. A label occupied a physical punched card or 80 bytes of precious DASD space. Medium-sized (by the standards of those days) assemblies took minutes and produced large paper listings. A label would consume two lines of printout, one for the label and one for the xref (and one more if the macro were local in the source file). I can easily envision someone saying "why did you code that label??? You didn't need to do that! You could have just coded *+12" Charles -----Original Message----- From: IBM Mainframe Assembler List [mailto:ASSEMBLER-LIST@LISTSERV.UGA.EDU] On Behalf Of Phil Smith III Sent: Friday, August 3, 2018 7:40 AM To: ASSEMBLER-LIST@LISTSERV.UGA.EDU Subject: Re: EQU * considered harmful Peter Relson wrote: >I have no evidence one way or the other, but I wonder whether the writers >of the "old" macros that used this style did so because they liked it (I >think we can all agree that we now hate it), or because they wanted to >avoid clutter of the listing or clutter of the XREF due to the extra >labels (thus increasing the size of the listing at a time when that >translated into a real cost of printing), or whether maybe assembler F >(that's the earliest IBM assembler I ever worked with) had limits that >they were worried about running aground upon, or ... >I wonder if it had to do with to label uniqueness. When labels were >limited to 8 characters (as they were at that time), even with &SYSNDX, >maybe there was some concern about interfering with a user-created label. >Nowadays, macroname_&SYSNDX is something we probably wouldn't mind >creating as a label. All good points. I think there was an element of keeping things cleaner/not having to scavenge for label uniqueness with 8-character labels. I don't remember who taught me the technique, though it must have been at UofW in the early 80s. I internalized it as "This isn't a 'real' branch-that is, we aren't going very far, just skipping a single instruction". And I would never, ever, ever consider doing it for more than one instruction.
