The OO concepts might be clearer in, e.g., ooREXX, Smalltalk. USING is a pseudo-op that tells the assembler how to translate between a symbolic address and a base-displacement pair. In its simplest form it is only a promise that particular registers will point to particular addresses. It's probably best that you master that form before trying dependent and labelled USING, but I strongly urge you to learn those as well.
-- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List [[email protected]] on behalf of Bob Bridges [[email protected]] Sent: Sunday, September 18, 2022 9:11 AM To: [email protected] Subject: Re: Assembler courses Twenty years ago I wrote a few programs for Excel, and didn't see what all the fuss was about: "object-oriented" didn't seem very different from traditional programming that I'd been doing for 25 years. (At the same time I was frequently infuriated at the message "...does not support this property or method", exactly because I ~didn't~ understand what was different about OO coding.) Eventually a VBA programmer advised me a bit more, and I'm now an enthusiast, about OO at least. Not so much about the Visual flavors of Basic itself, but it was my introduction to OO and it is at least available on all Windows machines and in all MS Office apps, which is handy. What confuses me (so far) is the concept of addressability in HLASM. Every time I make a stab at writing my first assembler program I get a little closer, but I'm still not there yet. In other assemblers I got quite familiar with indirect and offset addressing - it isn't that - but what exactly happens with the USING instruction still eludes me. --- Bob Bridges, [email protected], cell 336 382-7313 /* Revenge can be bitter-sweet. But if you sit back and watch, karma can be pure entertainment. -found on Facebook 2015 */ -----Original Message----- From: IBM Mainframe Discussion List <[email protected]> On Behalf Of Tom Brennan Sent: Sunday, September 18, 2022 00:59 As for programming, I seem to do better starting at the bottom, with instructions, registers, PSW bits and such, and moving up from there. Higher level languages and especially Object Oriented code tend to confuse me. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
