The lone C++ coder's blog - Emacs

Building cedet on Windows

nospam@example.com (Timo Geusch) — Wed, 27 Jan 2010 12:49:06 +0000

When building both cedet-1.0pre4 and -pre6 on Windows with cygwin and a fairly recent emacs 23.1-based Emacs-W32, a whole boatload of errors suddenly disappear when you make the following changes:

in Makefile, change "EMACS=emacs" to "EMACS=runemacs"
For good measure, also set "SHELL=bash", which is usually commented out

It goes without saying that it's a really good idea to disable any Cygwin version of emacs if you want to use Emacs-W32, too.

A couple of useful Emacs modes

nospam@example.com (Timo Geusch) — Tue, 06 Oct 2009 18:40:29 +0100

highlight-changes-mode – as the name implies, it highlights changes that you make to a file. I do find it useful for the typical scenario of checking out a file, making a couple of smaller changes to it and then having to diff it to work out what you actually changed. As mentioned over at Emacswiki it doesn’t play too nicely with font-locking but I’ll try out some of the suggestions in the “Taming Highlight-Changes-Mode” section on this page.

nxml-mode – my preferred mode for editing XML. Of course it would be better if I could be bothered to create schemas for some of the files I’m editing but even without them, it does a pretty good job. As it’s trying to parse the XML that you write, it’s very helpful when it comes to highlighting mismatched tags or auto complete tags.

ido-mode – I’ve only recently started to use it and I’m still trying to work out if it is useful enough for me or if the improved file finding capability does bother me more than it helps. Yes, I know it can do a lot more but so far I’m only using the improved file finding and buffer switching. I really rate the buffer switching which is the main reason I leave it turned on.

Not really a mode, but I like using bm.el for visible bookmarks. I don’t use bookmarks that often but the package is extremely useful when I do need them.

My emacs configuration file refactor

nospam@example.com (Timo Geusch) — Tue, 18 Aug 2009 13:27:35 +0100

In a previous post I described that a few months ago, I moved the third party elisp code under version control to make it easier to move it between machines and ensure a consistent configuration across them. The one remaining problem to solve was putting the configuration files (.emacs and .gnus.el) under version control. One of the approaches I really liked was described by Nathaniel Flath but I figured that it was too heavyweight for my needs.

What I ended up doing was to move the configuration files into version control and then simply change the basic dot-files to load the file from the subdirectory that is under version control. My .emacs now reads like this:


(load-file "~/emacs-lisp/dot-emacs.el")

Not the most elegant and automated version but it works for me.

How to use emacs to get rid of those pesky ^M characters

nospam@example.com (Timo Geusch) — Fri, 03 Jul 2009 11:09:42 +0100

I had another of these annoying mixed-mode DOS/Unix text files that suffered from being edited in text editors that didn't agree which line ending mode they should use. Unfortunately Emacs defaults to Unix text mode in this case so I had an already ugly file that wasn't exactly prettified by random ^M characters all over the place.

I also don't have the cygwin tools on the machine that I was seeing this problem on, I couldn't just run unix2dos or dos2unix over the file and be done with it, but at least I had emacs on that machine. So, emacs to the rescue again...

First, I used query-replace to get rid of the ^Ms in so the file was turned into a "proper" Unix text file. The trick here is that you need to use control-Q to quote the control character. In my case on a Windows box, the key sequence was M-Shift-% Control-Q Control-M and then use the empty string as a replacement value. Job done, we've now got a proper Unix mode text file. Well, after almost wearing out the 'Y' key but of course you can use replace-string instead.

In order to turn the Unix mode text file into a Dos mode one, run the command set-buffer-file-coding-system with the parameter undecided-dos and save the resulting file. Job done.

Emacs lisp packages under version control

nospam@example.com (Timo Geusch) — Sun, 03 May 2009 11:14:03 +0100

I've finally bit the bullet and stuck my various Emacs third-party libraries under version control in subversion. I don't normally modify third-party packages that I use but this allows me to quickly sync my Emacs configurations between machines. In order to make this work as smoothly as I intend it to work, there is one job left to do and that would be to create a common dot-emacs file that gets loaded by the local variants so I can have both some basic common customisations and machine-specific configurations at the same time.

While collecting all the Emacs packages that I want to put under version control I've also updated the weblogger mode that I use for my initial blog posting when I'm posting out of Emacs - the workflow looks something like writing post in Emacs using weblogger.el, post to the blog as a draft, then do the final editing and cleaning up in Serendipity's built-in editor. The version of weblogger.el I'm using is the version by Tom Robinson that's mentioned on EmacsWiki. I'm not using weblogger mode exclusively - I've also got the ScribeFire extension for Firefox installed, which is very handy if I just want to throw out a quick post linking to someone else's blog post - but I do like the combination of weblogger mode with Flyspell-mode and Auto-fill as they add up to a very useful text-only blogging solution.

Good article for CEDET beginners like me

nospam@example.com (Timo Geusch) — Wed, 25 Feb 2009 11:02:50 +0000

Alex Ott was kind enough to point me in the direction of an article he wrote on how to get started with CEDET. It's called A Gentle introduction to Cedet and I would certainly recommend reading it if you're interested in massively improving your Emacs/C++ environment. Of course the same goes for the other languages supported by CEDET but being mainly a C++ developer, this is of course where my main interest lies.

I guess I'll be downloading the development version of CEDET in the next couple of days then.

Looks like I unfairly blamed weblogger-mode

nospam@example.com (Timo Geusch) — Wed, 25 Feb 2009 06:40:58 +0000

Looks like I unfairly blamed my update of weblogger-mode for stripping out < and > from my HTML-formatted blog posts when I submit them using the xml-rpc interface and thus rendering any sort of HTML formatting more than slightly useless.

After some additional testing, it now seems that this is happening with other clients as well, at least when I'm submitting new posts to the blog. I think I should bite the bullet and update Serendipity to the latest release and then test again. And if it still doesn't work some PHP debugging might be in order. Oh well, looks like I blamed the wrong tool then...

Two more useful emacs modes

nospam@example.com (Timo Geusch) — Sun, 18 Jan 2009 19:19:00 +0000

Nothing really groundbreaking but something I found after reading Alex Ott's post on Cedet and looked at its website again. I had CEDET installed on several machines because JDEE requires CEDET and Semantic is part of that, but apart from the occasional use of the speedbar, I pretty much ignore CEDET and all its goodies.

Anyway, the above screenshot shows Emacs with semantic-tag-folding-mode (that'll be the little tringluar markers - note the 'folded' function) and which-func-mode (see modeline) enabled. Thanks to boost/iterator/iterator_adaptor.hpp for modelling the modes.

semantic-tag-folding-mode is a mode that uses the semantic package to analyse the code and suggest appropriate code folding. Very useful and much better than the old folding-mode.el which required you to edit the code and insert '{{{' and '}}}' in order to enable the folding functionality. Not really possible if you're looking at a codebase that's several thousand files, each one of them consisting of hundreds if not thousands of lines. The only potential problem with this mode compared to the old folding mode is that it only works for those languages that are supported by semantic.

which-func-mode, another of these little but very useful minor modes that displays the name of the current function in the modeline. Again, very useful when you're staring at files that are several thousand lines long and have functions whose length is measured in hundreds of lines.

Cool emacs tip over at emacs-fu

nospam@example.com (Timo Geusch) — Wed, 17 Dec 2008 11:02:49 +0000

If you and your colleagues use the famous "TODO", "FIXME" tags in comments in your code, the code snippet described in the this blog post might come in very handy. It's certainly something that'll find its way into my .emacs later today...

Another hooray for emacs

nospam@example.com (Timo Geusch) — Fri, 05 Dec 2008 16:20:10 +0000

This morning I attacked a problem that had been annoying me for quite a while. One project I'm working on has a rather big C++ code base with a large number of include files, strewn across a large number of subdirectories. So far, so good. Unfortunately the include statements didn't contain the partial paths of the form "subdir/include" which means that the compiler was passed include paths long enough to wrap a Christmas tree or two in. Not good.

Originally I didn't think much of this but when I tried to speed up the compile and started measuring compile times, I noticed that supplying these partial paths made a measurable difference to the compile time, at least when using Microsoft Visual C++. Of course this does make sense simply because the compiler has to search fewer directories to identify the correct file, but I was still surprised that the difference could be measured and was actually within a margin that I'd consider significant.

Continue reading "Another hooray for emacs"

Another reason why I'm not too keen on Aquamacs

nospam@example.com (Timo Geusch) — Sun, 31 Aug 2008 08:14:32 +0100

Obviously the big advantage of Aquamacs is that it visually integrates a lot better with Mac OS X than most of the other Emacs ports out there. Also, for better integration some of the keyboard bindings are changed out of the box, and this is where it falls apart for me. I am using a German keyboard layout on my Mac, which means that I need to use Option-something a lot to get at the special characters needed for programming, like '[' etc. Unfortunately these key bindings have been remapped in Aquamacs, which makes it a little problematic to use.

Yes, I know I can go and remap the keys again but my point is that it works out of the box with the other Emacsen available for the Mac, namely the Apple-supplied port and Carbon Emacs. That is a bit of a pity, but maybe it would be possible to offer 'standard Emacs key bindings' as an option when installing Aquamacs?

Weblogger Mode finally playing with Serendipity!

nospam@example.com (Timo Geusch) — Fri, 15 Feb 2008 20:14:32 +0000

Phew, that took a little while. After reading other people's stories as to how they got weblogger mode to play with their blogging system of choice, I made another attempt at getting it working properly, in other words without it eating the title.

After my Google mojo deserted me, I started looking at the code for both weblogger.el and xml-rpc.el to find what debugging helpers were available. Fortunately xml-rpc.el has a variable (xml-rpc-debug) that enables the user to view both the Lisp structure that is fed in and more importantly, the XML generated for the RPC call. This quickly pointed me in the right direction - for some reason, the entries sent didn't have a title node in the XML. Five minutes and some Lisp hacking later and it was clear that this was because the weblogger-capabilities setting (which weblogger.el fills in with the information retrieved from the server) was, well, empty, on account of getting no response from the server. And in that case, weblogger.el reverts back to the lowest common denominator (Blogger).

A poke around the source code for Serendipity's XML RPC handler plugin showed why - it doesn't support the mt.supportedMethods calls that weblogger mode uses to determine what the server can and can't do. Of course this wasn't a problem with the other blog clients I used as they relied on the user to specify the type of XML RPC Api used to communicate with the server.

A little bit of hacking and swearing (I don't really know PHP, so that didn't help) saw a handler for this call added and magically, the titles are now making it through OK. I'll try to email the maintainers of the plugin to see if they're interested in including the patch; depending on the outcome, I'll either put it up here for those interested or it'll come to Serendipity soon anyway.

Blogging with Emacs revisited - if you can read this, it worked

nospam@example.com (Timo Geusch) — Sun, 03 Feb 2008 21:38:57 +0000

I've mentioned this before, after using Drivel for a while I was looking for a way to post to my blog from inside (X)Emacs. I already use Emacs to post to newsgroups (using gnus) so why not use it to prepare posts to my blog as well? At the end of the day the majority of a blog posting is text, which should be spelled correctly and hopefully also include a few coherent thoughts, even though the latter may be conspicuously absent.

A recent posting on one of the Emacs newsgroups led me again to the EmacsWiki and more specifically the Journal editing section. This in turn led to WebloggerMode, which does allow me to post via XML-RPC and supports posting to various blog systems. As Serendipity uses the same format as Moveable Type, posting should work the same way as it does from Drivel. I am actually not using the "official" version of WebloggerMode, but the patched one from here. So far, the setup has worked so let's hope the posting does, too.

One of the main attractions to this mode is that it does support publishing in draft mode, which Drivel doesn't seem to support, and neither seem most of the other (free) clients I tried. As I normally write blog entries somewhere offline, revise it several times and then upload the entries to the blog, I do my final editing in Serendipity's editor. Having the blog entry published and then immediately afterwards publishing a correction seems to me as a bit backwards.

And yes, posting to the blog did work because otherwise, you wouldn't be seeing this text. The only part that didn't make it was the title of the entry but that's easily fixed when doing the final editing in Serendipity. It also seems that I do need to do a full markup of the entry itself (paragraphs et al) but that's not exactly a big issue, either. Nevertheless, I find the experience a tad underwhelming as several features that you'd hope/expect to work don't seem to. All I wasn't overly enamoured with weblogger mode, mainly because it didn't seem to be able to download the bodies of other entries when you're posting and asking it to retrieve the previous entry. Got the title alright, though, but that's a tad too asymmetric for my liking. Yes, I probably should have tried the unpatched version as well but life's a tad to short for trying all possible permutations. I also don't seem to be the only person having problems or issues with weblogger mode, so maybe it does need a bit more development.

More searching led me to BloGTK via this blog entry; It appears that I'm not the only one looking for a decent offline blog editor then. Photo posting isn't that important to me as you've probably noticed already, so it's something I could live without. It looks like it's possible to at least link to an image and that's good enough for me so far. Other than that it appears to be a relatively basic client, although in some respects it's less basic than Drivel. In others, it's possibly more basic as you have to mark up links by hand but that's something I can live with so far, especially as it supports the Extended entry bit that neither Drivel or most of the other clients I tried seem to support. Nevertheless it felt a bit basic, plus it's obviously Linux only, whereas I really would like to have a client that works in both Windows and Linux. Most of my machines are dual boot so only having to learn one client is a big advantage.

Enter my current editor of choice, Bleezer. It supports all the OSs I'm likely to use, it does seem to have most of the features that I need - the few missing are the "two parts" feature I liked so much about BloGTK and the 'publish to Draft' that weblogger mode allows for. Actually it can probably do the latter as I may have overlooked a config setting.

So, here you have it. A post that started out in Emacs, lost its title on the way, with some additions grafted on in BloGTK and the whole thing finalised in Bleezer.

Powered by Bleezer

Actually I was getting ahead of myself a little as I did end up having to edit the entry in Serendipity again. Unfortunately it appears that publishing via Bleezer doesn't turn on the comments and trackbacks functionality, so I had to go back in and edit the entry online anyway. Oh well. The search may well continue for a little while.

Tailing output in (X)Emacs

nospam@example.com (Timo Geusch) — Wed, 08 Aug 2007 14:18:23 +0100

Today, I needed to watch and analyse the output of a compile run on Linux - that's easy, right?

Well, it would've been if the build scripts for the project weren't so helpful as to automatically redirect the compiler output into a file, to preserve it for posterity. Not very helpful if you're trying to "just watch" the output. But as Emacs has a solution for just about everything, I had a poke around Google and the EmacsWiki to see if I could find something suitable.

Continue reading "Tailing output in (X)Emacs"