From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 10494 invoked by alias); 7 Oct 2011 16:04:48 -0000 Received: (qmail 10482 invoked by uid 22791); 7 Oct 2011 16:04:47 -0000 X-SWARE-Spam-Status: No, hits=-1.8 required=5.0 tests=AWL,BAYES_00 X-Spam-Check-By: sourceware.org Received: from relay1.mentorg.com (HELO relay1.mentorg.com) (192.94.38.131) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 07 Oct 2011 16:04:32 +0000 Received: from nat-ies.mentorg.com ([192.94.31.2] helo=EU1-MAIL.mgc.mentorg.com) by relay1.mentorg.com with esmtp id 1RCCuV-0003Z0-Jb from pedro_alves@mentor.com ; Fri, 07 Oct 2011 09:04:31 -0700 Received: from scottsdale.localnet ([172.16.63.104]) by EU1-MAIL.mgc.mentorg.com with Microsoft SMTPSVC(6.0.3790.1830); Fri, 7 Oct 2011 17:04:29 +0100 From: Pedro Alves To: gdb@sourceware.org Subject: Re: Python and structured output from breakpoint_ops Date: Fri, 07 Oct 2011 16:04:00 -0000 User-Agent: KMail/1.13.6 (Linux/2.6.38-11-generic; KDE/4.7.1; x86_64; ; ) Cc: Tom Tromey References: In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Message-Id: <201110071704.27691.pedro@codesourcery.com> X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2011-10/txt/msg00042.txt.bz2 On Friday 07 October 2011 16:39:59, Tom Tromey wrote: > Phil> So again we are limited to a string and a constant. I guess we could, > Phil> if the user passed a list within a list, call ui_out_list there. But to > Phil> me, you will only ever want this output on one line (in fact, it may be > Phil> a requirement, I am not to sure). > > I don't think it has to be. > > Phil> There seems to be more room to maneuver with print_mention, and > Phil> print_one_detail. They are currently implemented as pure strings. But > Phil> again, both I believe (and really, I want) to be implemented as a single > Phil> string. print_mention is called when a breakpoint is created. Is there > Phil> an example of what kind of structured output we could use here? > > I think I was hoping that we could unify some of the print methods. It > seems strange to have 4 different method to print more or less the same > basic information. I still think we should cleanup the breakpoint printing machinery before exporting it to python. These methods were not converted to breakpoint_ops yet. By only considering a single string, you're leaving out breakpoints with multiple locations. And those will become even more important with Tom's linespec/multi-location rework. > This might mean constraining the output a little bit in order to provide > a simpler API. I think that would be good, but that is just my opinion; > however, if it turned out to be too limiting we could always extend the > options later. > > Even if all the methods can't be unified it seems that at least > print_one and print_one_detail could be. > > Phil> print_one_detail is an optional detail line below each entry for "info > Phil> breakpoints". This has to be limited to a single line, to remain > Phil> constant with "info breakpoints" output. > > It seems like it could have multiple lines, just nothing does this yet. Yeah. Random catchpoints are likely to want it. > This is a good example of where structured output is useful: right now > the code has to know how to format the continuation lines (e.g., start > with a tab) -- but it seems like it would be better not to bake this > into Python scripts everywhere, in case we want to change the "info > break" formatting in the future. Some kind of structured result would > let us do this. Yeah. I'd like that direction. It'd allow for more smarter column/cell wrapping too. > Phil> In fact, if you look at the mi command -break-list, it just maps > Phil> to info break and captures that output. Maybe that conversation > Phil> is what Jan was talking about when there is an explicit mention > Phil> that any field change has to be made by Vlad? The thing is that the fields that are output aren't constrained at all by the "address" / "what" columns you see in the CLI. Look at all the "ui_out_*" calls. It seems quite reasonable to me to be able to output random fields from python too, so you could implement new breakpoint/catchpoints in python and forward whatever necessary info to the frontend through MI. -- Pedro Alves