OOREXX now allows the equivalent of expressions in tails: stem[tail expression]
If X is a floating point (REAL) variable, why shouldn't x**(-1) be legal? A for using a floating point variable as a control variable, I have no sympathy. In the real world, measuring devices have errors and you should never expect equality of floating point numbers. I have never seen DWIM. I have seen Do what I didn't mean but he erroneously assumed I meant (DWIDMBHETIM). -- 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: Thursday, July 18, 2019 12:41 PM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Where put the notional constant in a condition (Was RE: JCL COND Parameter) On Tue, 16 Jul 2019 19:22:51 +0000, Seymour J Metz wrote: > >The cardinal sin in language design is to make the compiler simpler at the >expense of the user. ... > I see a notable example of this in Rexx's not supporting expressions in compound symbol tails which some have justified as making recognition of assignments easier. OTOH, Pascal declined to provide an exponentiation operator in order to expose to programmers the underlying costly implementation: X ** Y is implemented in other languages as exp( log( X ) * Y ) Physics graduate students complained to me when the FORTRAN runtime threw an exception on X ** 2.0 when X was negative. "Why can't I square a negative number?" (Some BASIC interpreters take special paths when a number has an integral value.) And they complained when (FORTRAN, but easier in C pseudocode): for ( X = 0; X!=1.0; X+=0.1 ) { ...; } ... never terminated. "Roundoff error!? Why doesn't it just use the exact value of one tenth?" DWIM? -- 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
