Path: csiph.com!news.swapon.de!fu-berlin.de!uni-berlin.de!not-for-mail From: Terry Reedy Newsgroups: comp.lang.python Subject: Re: Application console for Tkinter program? Date: Sun, 6 Mar 2016 07:12:43 -0500 Lines: 37 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: news.uni-berlin.de 2jafutqEil0Quucf3eDpFQ5TI1MRulgyR/hwIl7ZbadA== Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.000 X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'python,': 0.02; 'expressions': 0.07; 'instance.': 0.09; 'mode,': 0.09; 'prefixed': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'repl': 0.09; 'statements': 0.09; 'subclass': 0.09; 'subclasses': 0.09; 'toplevel': 0.09; 'python': 0.10; 'assume': 0.11; 'jan': 0.11; 'syntax': 0.13; 'result.': 0.15; 'compile,': 0.16; 'eval': 0.16; 'idle,': 0.16; 'idlelib': 0.16; 'interacting': 0.16; 'out?': 0.16; 'received:80.91.229.3': 0.16; 'received:io': 0.16; 'received:plane.gmane.org': 0.16; 'received:psf.io': 0.16; 'reedy': 0.16; 'subject:Tkinter': 0.16; 'subject:program': 0.16; 'subprocess': 0.16; 'useless': 0.16; 'wrote:': 0.16; 'later': 0.16; 'example.': 0.18; 'widget': 0.18; 'shell': 0.18; 'runs': 0.18; 'assign': 0.22; 'exec': 0.22; 'parse': 0.22; 'am,': 0.23; 'code,': 0.23; 'code.': 0.23; '(or': 0.23; "haven't": 0.24; 'header:In-Reply-To:1': 0.24; 'header:User-Agent:1': 0.26; "doesn't": 0.26; 'header:X-Complaints-To:1': 0.26; 'entered': 0.27; 'least': 0.27; 'actual': 0.28; 'lot.': 0.29; 'mode.': 0.29; 'print': 0.30; 'code': 0.30; 'class.': 0.30; 'run': 0.33; 'class': 0.33; 'source': 0.33; 'idle': 0.33; 'traditional': 0.33; "i'll": 0.33; 'thanks!': 0.34; 'could': 0.35; 'text': 0.35; 'instance': 0.35; 'but': 0.36; 'too': 0.36; 'should': 0.36; 'instead': 0.36; '(and': 0.36; 'modules': 0.36; 'to:addr:python-list': 0.36; 'subject:?': 0.36; 'subject:: ': 0.37; 'display': 0.37; 'received:org': 0.37; 'difference': 0.38; 'christian': 0.38; 'skip:p 20': 0.38; 'does': 0.39; 'application': 0.39; 'to:addr:python.org': 0.40; 'still': 0.40; 'details': 0.62; 'received:96': 0.63; 'complete': 0.63; 'between': 0.65; 'believe': 0.66; 'state.': 0.72; 'gollwitzer': 0.84; 'received:fios.verizon.net': 0.91; 'browse': 0.96 X-Injected-Via-Gmane: http://gmane.org/ X-Gmane-NNTP-Posting-Host: pool-96-227-207-81.phlapa.fios.verizon.net User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 In-Reply-To: X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Xref: csiph.com comp.lang.python:104133 On 3/6/2016 4:23 AM, Christian Gollwitzer wrote: > Am 05.03.16 um 22:16 schrieb Terry Reedy: >> Not now. A console is a REPL + text display to read from and print to. >> The actual IDLE REPL is PyShell.ModifiedInterpreter, which subclasses >> stdlib code.InteractiveInterpreter. Most of the additions are for >> interacting with the subprocess that runs user code. You should start >> instead with the base class. >> >> The Shell text display is a subclass of a subclass of a class that >> contains a subclass of Toplevel with the complete IDLE Menu and a Text >> widget wrapper. Again, this is too much baggage for an application >> console. >> >> The idlelib ColorDelegator syntax highlighter can be reused with a Text >> instance. See turtledemo.__main__ for an example. I don't know if (or >> how) IDLE's autocompletion modules could be reused in their current >> state. I believe Shell's history 'list' consists of the statements in >> the Text instance prefixed by the '>>> ' prompt. > > Thanks! I'll try to browse my way through the source code, these details > help a lot. I still haven't understood the difference between exec() and > eval(). I understand that for statements you want to exec them, for > expressions you eval it and print the result. When the user has entered > code, how does the REPL know if it should be eval'ed or exec'ed? I > assume that you don't try to parse the Python code manually to find this > out? Or you try to eval(), and if it doesn't compile, you exec()? Python expressions are also statements. Python REPLs exec statements. But to make Read-Exec-Print work like traditional Read-Eval-Print, Python, in interactive mode, echos the value of expression statements (and assign it to _ for later reuse). So '2 + 2' echos 4 in REPL, or at least in the console and IDLE, '2 + 2' is useless in a program run in batch mode. -- Terry Jan Reedy