Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!news.glorb.com!peer03.iad.highwinds-media.com!news.highwinds-media.com!feed-me.highwinds-media.com!border1.nntp.dca1.giganews.com!nntp.giganews.com!news.iecc.com!.POSTED!nerds-end From: news@iecc.com (News Subsystem) Newsgroups: comp.compilers Subject: Re: parsability Date: Mon, 9 Feb 2015 14:37:46 +1100 Organization: Compilers Central Lines: 40 Approved: comp.compilers@iecc.com Message-ID: <15-02-021@comp.compilers> References: <10-11-017@comp.compilers> <15-02-009@comp.compilers> <15-02-011@comp.compilers> <15-02-017@comp.compilers> <15-02-019@comp.compilers> NNTP-Posting-Host: news.iecc.com Mime-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=response Content-Transfer-Encoding: 8bit X-Trace: miucha.iecc.com 1423550947 68744 2001:470:1f07:1126:0:676f:7373:6970 (10 Feb 2015 06:49:07 GMT) X-Complaints-To: abuse@iecc.com NNTP-Posting-Date: Tue, 10 Feb 2015 06:49:07 +0000 (UTC) Keywords: history, design Posted-Date: 10 Feb 2015 01:49:07 EST X-submission-address: compilers@iecc.com X-moderator-address: compilers-request@iecc.com X-FAQ-and-archives: http://compilers.iecc.com rFom: "Robin Vowels" X-Received-Bytes: 2900 X-Received-Body-CRC: 1653075787 Xref: csiph.com comp.compilers:1523 From: "Hans-Peter Diettrich" Sent: Monday, February 09, 2015 6:49 AM > Robin Vowels schrieb: > >> A number of special characters have traditionally acquired multiple uses. >> The asterisk, parentheses, apostrophe, colon, period, feature heavily >> on account of the limited number of characters available in equipment >> of the era (48-character set, 60 character set, etc.) and continue to do so >> for historical reasons. > > IMO the real and persistent limit is the keyboard, with a limited number > of keys. Present keyboards for the PC have keys for 33 special characters (in addition to upper and lower-case and digits). That's twice as many in use in languages. > Increasing the number of keys is not a solution, because then > it may be more time consuming to find an special key, instead of reusing > a character or typing more characters. No need to increase the number of keys. Recall old typewriters? Some had provision for three shifts (lower-case, upper-case, and special characters). The same could be done with computer keyboards (well, it's sort of done with the normal, caps, and CTRL keys). A proper third shift key with corresponding glyphs inscribed on the keys could extend the range of special characters. After all, there is provision for 256 characters encoded in a byte, and we use only half of them. >Why didn't APL succeed in the long run? Because it was write once throw-away language. Programs were largely unintelligible to all except the writer. This email probably contains viruses and malware despite what avast! Antivirus protection says. [It was perfectly possible to write readable APL programs, but almost nobody did. -John]