The inappropriate absence or use of quotes will break the code. I don't know whether ICCF is comparable, but with ISPF it is bog standard to use ISPEXEC and ISREDIT commands that require the names of variables.
With EXECIO, adding quotes will either fix *or break* the code, depending on what the code is doing. There is no substitute for understanding and *accurately* explaining the rules of the language, and that is by no means limited to REXX. -- Shmuel (Seymour J.) Metz http://mason.gmu.edu/~smetz3 ________________________________________ From: IBM Mainframe Discussion List [IBM-MAIN@LISTSERV.UA.EDU] on behalf of Tony Thigpen [t...@vse2pdf.com] Sent: Friday, June 5, 2020 2:35 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Gratuitous EXECIO Documentation To say it another way. Normally the use of quotes around a variable will *break* the code. With EXECIO, use of quotes will *fix* the code. Tony Thigpen Tony Thigpen wrote on 6/5/20 2:29 PM: > No, the problem is not an understanding of how REXX evaluates expressions. > > The problem is that EXECIO is one of the few places that a variable NAME > is an operand, not the variable CONTENTS. > > Tony Thigpen > > Seymour J Metz wrote on 6/5/20 2:11 PM: >>> Your statement implies that "sometimes" it is legitimate to not use >>> quotes. >> >> In fact, sometimes it is mandatory to not use them. >> >> Your suggested wording has the same issue as what is in the manual; it >> prescribes rules that aren't always appropriate. The REXX Reference >> manual has a perfectly adequate description of how REXX evaluates >> expressions: refer the reader to that. Don't invent rules that >> sometimes don't apply. >> >> The root problem is that someone is writing code without understanding >> the language. >> >> >> -- >> Shmuel (Seymour J.) Metz >> http://mason.gmu.edu/~smetz3 >> >> ________________________________________ >> From: IBM Mainframe Discussion List [IBM-MAIN@LISTSERV.UA.EDU] on >> behalf of Tony Thigpen [t...@vse2pdf.com] >> Sent: Friday, June 5, 2020 2:03 PM >> To: IBM-MAIN@LISTSERV.UA.EDU >> Subject: Re: Gratuitous EXECIO Documentation >> >> Sorry, but I disagree. >> >> Your statement implies that "sometimes" it is legitimate to not use >> quotes. I would say that "sometimes you can get lucky and get away with >> not using quotes". :-) >> >> A very basic documentation statement would be: >> Some formats of the EXECIO command may reference a variable >> by the name of the variable. Such references should be >> within quoted text. Such an example is the variable name >> of a stem variable: >> Correct: >> 'EXECIO 5 DISKW' ddname '(STEM MYSTEM.' >> Incorrect: >> 'EXECIO 5 DISKW' ddname '(STEM' mystem. >> Use without quotes can result in unpredictable results. >> >> >> I really think this is the root problem, not the fact that someone >> defined a variable with the same name as a common keyword, such as your >> example with "STEM". Such an example is just part of the language >> restriction and not directly related to EXECIO. >> >> >> Tony Thigpen >> >> Seymour J Metz wrote on 6/5/20 12:56 PM: >>> My problem with gratuitous documentation is that they invariably get >>> it wrong. Describe the actual requirements and direct the reader to >>> the appropriate places for details. In this case, something like: >>> >>> As with any command issued to an external environment, ensure >>> that the >>> expression you use evaluates to the intended EXECIO command. In >>> particular, it may be prudent to always quote keywords to avoid >>> confusion with variables with the same name. For example, if >>> you assign >>> the variable "stem" to a value other than 'STEM' and then use >>> >>> EXECIO 5 DISKW ddname '(' STEM >>> >>> instead of >>> >>> EXECIO 5 DISKW ddname '( STEM' >>> >>> in your code, you will not invoke the correct command. >>> >>> Would be reasonable if they have to spell it out. >>> >>> >>> >>> -- >>> Shmuel (Seymour J.) Metz >>> http://mason.gmu.edu/~smetz3 >>> >>> ________________________________________ >>> From: IBM Mainframe Discussion List [IBM-MAIN@LISTSERV.UA.EDU] on >>> behalf of Paul Gilmartin >>> [0000000433f07816-dmarc-requ...@listserv.ua.edu] >>> Sent: Friday, June 5, 2020 11:29 AM >>> To: IBM-MAIN@LISTSERV.UA.EDU >>> Subject: Gratuitous EXECIO Documentation >>> >>> In: >>> https://www.ibm.com/support/knowledgecenter/SSLTBW_2.3.0/com.ibm.zos.v2r3.ikja300/dup0037.htm >>> >>> >>> I see the verbiage: >>> When you use EXECIO, you must ensure that you use quotation marks >>> around any operands, such as DISKW, STEM, FINIS, or LIFO. Using >>> quotation marks prevents the possibility of the operands being >>> substituted >>> as variables. For example, if you assign the variable stem to a >>> value in >>> the exec and then issue EXECIO with the STEM option, if STEM is >>> not >>> enclosed in quotation marks, it is substituted with its >>> assigned value. >>> >>> Sheesh! A similar caution might be included for any command in the >>> Ref., >>> but it doesn't belong. >>> >>> "must ensure"? Well, not always. >>> >>> I infer the etiology: A troublesome user once coded: >>> STEM=SKIP /* perhaps */ >>> EXECIO ... >>> ... got astonishing results; went to SR; got fully proper "REJ; RTFM"; >>> vindictively submitted RCF. A feckless tech writer acceded and added >>> the paragraph. >>> >>> I strongly suspect the matter is covered properly earlier (citation >>> needed) >>> in the Ref., which shouldn't be cluttered with such errant rubbish. >>> >>> (I was reading that Ref. to see whether EXECIO assembles segments >>> of V[B]S records. Didn't find it.) >>> >>> -- gil >>> >>> ---------------------------------------------------------------------- >>> For IBM-MAIN subscribe / signoff / archive access instructions, >>> send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN >>> >>> ---------------------------------------------------------------------- >>> For IBM-MAIN subscribe / signoff / archive access instructions, >>> send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN >>> >> >> ---------------------------------------------------------------------- >> For IBM-MAIN subscribe / signoff / archive access instructions, >> send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN >> >> ---------------------------------------------------------------------- >> For IBM-MAIN subscribe / signoff / archive access instructions, >> send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN >> > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
