No, that conflates things that happe ned at very different times. First, OS/360 had DSN=&foo for temporary datasets.
S/360 added symbolic parameters on the PROC and EXEC statements. As part of that, &name is replaced with the value of the referenced parameter if it exists, and otherwise left as is. A double ampersand is replaced with a single ampersand. As long as you don't have foo=bar, DSN=&foo works like it always did, but you can code it DSN=&&foo just in case. Then, decades later, // SET came along, with similar rules.. ________________________________________ From: IBM Mainframe Discussion List <[email protected]> on behalf of Mike Schwab <[email protected]> Sent: Wednesday, August 30, 2023 4:59 PM To: [email protected] Subject: Re: Threading (was: LISTSERV Trivia: Deleting drafts?) On Wed, Aug 30, 2023 at 3:32 PM Paul Gilmartin <[email protected]> wrote: > And I've seen no good explanation for "&&TEMPDSN" > S/360 started with &tempdsn. Later (S/360-370), // SET VAR=value was added. Created &&tempdsn is always &tempdsn. &var picks up the SET value and if none is specified it uses the name of the var. -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? ---------------------------------------------------------------------- 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
