Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!gegeweb.org!de-l.enfer-du-nord.net!feeder2.enfer-du-nord.net!feeds.phibee-telecom.net!newsfeed.xs4all.nl!newsfeed6.news.xs4all.nl!xs4all!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.041 X-Spam-Evidence: '*H*': 0.92; '*S*': 0.00; 'sure.': 0.05; '>>>>': 0.09; 'none)': 0.09; 'return,': 0.09; 'though...': 0.09; 'am,': 0.12; 'received:209.85.210.174': 0.13; 'received:mail- iy0-f174.google.com': 0.13; 'protocol': 0.15; '(eg': 0.16; '127': 0.16; 'anyone?': 0.16; 'cursor': 0.16; 'from:addr:rosuav': 0.16; 'from:name:chris angelico': 0.16; 'sliced': 0.16; 'advance': 0.17; 'wed,': 0.17; 'language': 0.17; 'wrote:': 0.18; 'posting': 0.20; 'subject:not': 0.21; 'dec': 0.22; 'header:In-Reply-To:1': 0.22; 'defined': 0.24; "i'm": 0.26; 'message-id:@mail.gmail.com': 0.28; 'eating': 0.30; 'version': 0.32; 'propose': 0.32; 'implement': 0.32; "can't": 0.32; 'to:addr:python-list': 0.34; 'character': 0.34; 'then.': 0.34; 'however,': 0.36; 'question': 0.36; 'received:google.com': 0.37; 'some': 0.38; 'received:209.85': 0.38; 'getting': 0.38; 'characters': 0.39; 'clearly': 0.39; 'should': 0.39; 'johnson': 0.39; 'why': 0.39; "it's": 0.40; 'received:209': 0.40; 'to:addr:python.org': 0.40; '2011': 0.61; 'your': 0.61; 'back': 0.62; "we've": 0.62; 'movement': 0.64; 'internet': 0.64; 'exact': 0.68; 'paper': 0.72; 'greatest': 0.73; 'hundred': 0.74; '20th': 0.77; '12:21': 0.84; 'archaic': 0.84; 'feed,': 0.84; 'observer': 0.84; 'bread': 0.91; 'century': 0.91; 'holes': 0.91 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=Gvikpr0vpPhw0iPuB6GPVWArj8p1m9jRZOtbaBQuLSI=; b=ef6DRJGlo0fHy3SSMvM5p6BON4AvQqSPhiq8zEjpNcfv4SDfjr50EX5qHbCrRpYhlM A6YmyHxupXeKaiImhk/dO6pW+qvYxUaqYdWnrCJHE+f+g4O4kr1/5K6fB5e8XjishbtJ 56bEUGnOVHN6O6gnmbXER9GBjGEwB1zCfVL3Q= MIME-Version: 1.0 In-Reply-To: References: <4edcecc6$0$29988$c3e8da3$5496439d@news.astraweb.com> Date: Wed, 7 Dec 2011 01:03:55 +1100 Subject: Re: Backspace does not erase in stdout From: Chris Angelico To: python-list@python.org Content-Type: text/plain; charset=ISO-8859-1 X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 35 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1323180238 news.xs4all.nl 6928 [2001:888:2000:d::a6]:50417 X-Complaints-To: abuse@xs4all.nl Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:16732 On Wed, Dec 7, 2011 at 12:21 AM, Rick Johnson wrote: > *Wise Observer Speculates:* Why on earth are we "21st century slaves" > to an archaic mid 20th century technology that punches holes in paper > tape? Anyone? > >>>> isinstance(Progress, None) > True I'm not sure. Let's see... * Manned, powered, heavier-than-air flight: A hundred years. * TCP/IP: Thirty years. * Sliced bread: Eighty years. (What was the greatest thing BEFORE sliced bread?) * The English language: A few hundred, depending on how you count Why are we still eating sliced bread on board aeroplanes while posting in English on internet forums? Clearly we've made no progress since then. What language and communication protocol do you propose for the new python-troll-list? Getting back to the point though... The use of 127 for DEL is a consequence of the exact technology of paper tape. However, the question of whether BS is destructive or not is separate. Should it parallel other characters (draw character at cursor then advance cursor, vs retard cursor then erase character at cursor), or should it parallel cursor movement (eg carriage return, line feed, vertical tab)? If your BS is defined nondestructively, you can implement the destructive version with three characters; if it's defined destructively, you can't implement a nondestructive without some fiddliness (some systems use characters 28-31 for cursor movement). ChrisA