From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,bc1361a952ec75ca X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-07-31 19:29:51 PST Path: archiver1.google.com!newsfeed.google.com!newsfeed.stanford.edu!newsfeed.berkeley.edu!news-hog.berkeley.edu!ucberkeley!newshub.sdsu.edu!newspeer.cts.com!galanthis.cts.com!127.0.0.1.MISMATCH!not-for-mail Sender: kst@king.cts.com Newsgroups: comp.lang.ada Subject: Re: The concept of := (was How to make Ada a dominant language) References: <3B6555ED.9B0B0420@sneakemail.com> <87n15lxzzv.fsf@deneb.enyo.de> <3B672322.B5EA1B66@home.com> From: Keith Thompson Date: 31 Jul 2001 19:29:50 -0700 Message-ID: X-Newsreader: Gnus v5.5/Emacs 20.3 NNTP-Posting-Host: 209.68.192.180 X-Trace: 996632990 nntp.cts.com 285 209.68.192.180 Xref: archiver1.google.com comp.lang.ada:10907 Date: 2001-07-31T19:29:50-07:00 List-Id: Here's some more background on the use of ":=" for assignment. The following is an excerpt from a presentation given by Alan J. Perlis at the ACM SIGPLAN History of Programming Languages Conference in 1978. So both proposals had these constructions as their basis, and they differed only in rather small details, some of which have turned out to be more important than others. For example, the Americans, following the FORTRAN appropach, had the variable being assigned on the left. The Europeans had it on the right. The Americans used an equals sign for the assignment, thus hiding the fact that there is a direction to the assignment; the Europeans used a directed arrow pointing to the right. When ALGOL 58 came out, neither equals nor directed arrow was used, but a colon-equal and it pointed to the left. -- Keith Thompson (The_Other_Keith) kst@cts.com San Diego Supercomputer Center <*> Cxiuj via bazo apartenas ni.