"ELSE IF ¬TRUE THEN <whatever else>" was just to demonstrate that "TRUE" is Boolean.
On 07/09/2020 05:24, Seymour J Metz wrote: > First, that code is highly obfuscated. Why would you ever want to write "IF > foo & TRUE" instead of "IF foo"? > > Second, "ELSE IF ¬TRUE THEN foo" is dead code. > > Third, there are no booleans in REXX; the only data type is character string. > > > -- > Shmuel (Seymour J.) Metz > http://mason.gmu.edu/~smetz3 > > > ________________________________________ > From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> on behalf of > CM Poncelet <ponce...@bcs.org.uk> > Sent: Sunday, September 6, 2020 9:31 PM > To: IBM-MAIN@LISTSERV.UA.EDU > Subject: Re: REXX true/false (was Constant Identifiers) > > In the following example, > TRUE = (1 - 1 = 0 & 1 ¬= 0) [or whatever is more appropriate], > it is then sufficient e.g. to code: > IF 4 ¬= 6 & TRUE THEN <whatever> > ELSE IF ¬TRUE THEN <whatever else> > > I.e. TRUE can be defined as a Boolean '1'b in REXX, as per above. > > On 06/09/2020 20:43, Paul Gilmartin wrote: >> On Sun, 6 Sep 2020 12:03:18 -0400, scott Ford wrote: >> >>> I have done things like true =‘Y’ and then >>> >>> If true >>> .......... >>> end >>> >> What language? That would certainly be a syntax error in Rexx. >> And why? You could just omit the "if true" and code: >> do >> .......... >> end >> >> >> n Sun, 6 Sep 2020 17:39:48 +0000, Seymour J Metz wrote: >>> A simple true=1;false=0 should suffice for clarity. >>> >> Perhaps not to someone most familiar with shell scripts >> where the definitions are nearly the opposite (command >> status ($?) = 0 means success or true). >> >> >> On Sun, 6 Sep 2020 17:43:04 +0100, Rupert Reynolds wrote: >>> The advantage of Boolean is clarity in something like:- >>> /* Rexx */ >>> TRUE = (1=1) >>> ... >>> SELECT >>> WHEN logmode = "D4A32782" & (GotASCII & GotVBMrecord) THEN do >>> ... >> Continuing your example, how would you have set the variables >> "GotASCII" and "GotVBMrecord" using the quasi-constants TRUE >> and FALSE? Does that enhance either clarity or economy of >> expression? >> >> I'm thinking that something like: >> if filetype=='ASCII' then GotASCII = TRUE; else GotASCII = FALSE >> would more succinctly be written: >> GotASCII = ( filetype=='ASCII' ) >> >> But I've seen even worse, such as: >> if GotASCII = true then ... >> rather than simply: >> if GotASCII then ... >> >> >> On Sun, 6 Sep 2020 19:28:11 +0000, Seymour J Metz wrote: >>> Yes, you can count on the truth values of 0 and 1 in REXX never changing. >>> >> Only if I spent $60 for the ANSI Standard .pdf >> >> -- 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
