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» Will code for food

Tue, 12/22/2009 - 05:34

Ha, what a bit of a bribe can do to me… Someday earlier today a user of the PHP plugin for KDevelop brought up the flickering issue in it again. Well as I told him: I myself find it very annoying and wanted to fix it since quite some time, but never got around to it… Usually that would be it and I’d go watch some more FamilyGuy until I’m in the mood to track this bugger down. But well, thankfully Phlogi wasn’t so easy to dispatch:

<Phlogi> milian: ok… I’ll send you pizza and beer if you fix this!

Hours of gdb sessions later, I finally committed a fix. So Phlogi, if you read this: You owe me ;-)

To all others: If you tried the PHP plugin out and the flickering was too much for you: Give it a try again! I’m personally totally overwhelmed, the difference is huge! I often perceived the PHP plugin to be magnitudes slower than the C++ one. Well, looks like most of this was only due to the flickering. Now things are much smoother.

Happy holidays!

» Real FOSS appreciation

Mon, 12/07/2009 - 03:25

So, it’s been roughly a year since my first commit to kdelibs. According to Ohloh it’s been in November 2008. And boy have I learned much in this year. I learned C++ just to be able to contribute to KDE, since I thought it would be awesome to be able to “fix your own itch”. I have to say: It was the best decision I ever made.

I really came to appreciate FOSS in a whole new light: Contributing to a big project like KDE gets you in contact with lots of nice people. And they will help you get things done. What’s better is that in the process you learn lots of things. And I mean lots. I can now use GDB, Valgrind, now my way around some parts of the KDE/Qt API, can investigate performance related questions… And since these are such huge topics, there’s always more to learn, much more!

I doubt someone could learn that much by reading books or writing his own little application without the help of a community. The wealth of possibilities inside KDE will increase your horizon constantly. And there is tons of very good code to study! Want to know why something is not working? Look at the source. Still not helping? Ask your fellow developers. I really have to say it’s an awesome feeling to be part of this big community.

Fixing an itch: Qalculate! backend for Cantor

You know, I’m officially a Physics student, I just happen to be way more interested in programming (the practical part of it, not really that much the theoretical part).

Since I started with Physics two years ago, I always required a good calculator, esp. for experimental physics. The best calculator I found was Qalculate!, especially it’s great support for units and constants made me solve tedious exercises in a fraction of the time it required my fellow students that could not use Qalculate (it only runs on Linux). Really, it’s an outstanding piece of software in my opinion.

But to get to the point: Qalculate was the last KDE 3 app on my desktop, and I wanted to change that. Now I read about Cantor, esp. once fellow KDevelop hacker Apol wrote about his KAlgebra backend for Cantor, and I knew: This is the perfect fit for libqalculate!

So last week I started and already have a somewhat working backend available:

http://websvn.kde.org/trunk/playground/edu/cantor-backends/qalculate/

This once again showed the utterly insane greateness of FOSS: I started to hack on the backend and looked at the existing backends for guidance. I also contacted arieder, the author of Cantor, directly and chatted with him, getting help. But I did not only /take/. I reviewed his API, gave suggestions, reported whishes and bugs and eventually hacked a little bit on the sources themselves. Imagine this in a corporate environment: I’d probably have had to report in some shabby tracker and wait ages for my feature request to be closed as wontfix…

And while writing the backend I had this realization that also triggered this blog post: I actually did something useful in a few days. I could never have imagined being in that position one year ago. I always thought that C++ was a bit of black magic, especially writing things from scratch. But now… Now I’m somehow able to grasp code and come up with something working in a few days.

The problem this brings, is of course that you can easily loose track and overload yourself with work… I could spent lots of hours in any part of KDE. My TODO alone bears for KatePart, KDevelop-PHP, KDevelop itself, Quanta, …. You name it! I think this will become a fun holiday ;-)

PS: Just a quick note: I really think that Cantor will become a great and useful application for science students. It will be your central application for any calculations, either numeric (e.g. Qalculate) or symbolic (e.g. Maxima).

» KDevelop & KWrite/Kate hacksprint 2010 in Berlin

Mon, 11/16/2009 - 16:38

Hey everybody!

If you are a KDevelop and/or Kate/Kwrite developer and do not read the mailing lists: There’s a hack sprint coming up in Berlin in 2010. I think there’ve been enough sprints in Berlin already so that you know it’s a great city for such an event. Though this time it won’t be at KDAB or Nokia offices, but at the Physics Faculty of the FU-Berlin. Since I (currently) work there as an IT admin, it was my first choice and worked out. I hope it will be a good location for the meeting. If you want to attend, vote on doodle:

http://www.doodle.com/vkyh9up9794zr4s8

But you probably also should register either on the KDevelop or KWrite mailing lists so I have some kind of way to contact you.

PS: in unrelated news I’ll do an internship at KDAB next year! yay

» KDevelop Hack Sprint

Thu, 04/02/2009 - 01:38

Huzza! The KDevelop Hack Sprint 09 is now official.

Thanks to the huge engagement of Alexander Dymo we will meet from the 19th to 26th April 2009. The meeting will take place at Alexander’s university, the national university of shipbuilding in Odessa Mykolayiv, Ukraine. Thanks to the people there responsible for making this sprint possible by providing us with the premises, internet, power etc.

Since this is my very first Hack Sprint and considering that I only recently started contributing to KDE in general and KDevelop in particular I am very excited. The topics I will plan to hack on include (all related to PHP language support plugin):

  • add auto completion after require(_once) and include(_once), just like it works for #include in CPP
  • add auto completion of PHP statements (think echo, exit, require(_once, include(_once) etc. pp.)
  • add auto completion for build-in PHP keywords
  • fix auto completion of interfaces / classes after the keywords implements and extends (working on that right now)
  • fix KDevplatform and the Generic Plugin Manager to support remote projects, i.e. via fish or ftp (or anything else supported by KIO)

Since I’ll have a whole week of hacking time I hope to get all that done. And more. Since another great thing about the Sprint will be that I can finally meet Niko (nsams) in person. For those of you who don’t know: He’s the one who started the PHP language support plugin. Expect some additional points from our roadmap getting implemented / fixed during that time!

Furthermore it looks like Mr DUChain himself - David Nolden - will attend as well. I have some ideas regarding parts of the PHP plugin I want to refactor but need additional insight to the way the DUChain works. Let’s see if David and I can work it out.

And maybe I can even take a look at Quanta 4 itself… Let’s see!

I’m very much looking forward to the Sprint and meeting some of the other developers! And much thanks again to Alexander for planning all this. Oh and also a very great Thank You goes to the KDE e.V. for sponsoring the event. I wouldn’t have been able to attend otherwise!

Keep an eye on the planet for more blog posts during the Hack Sprint, I’ll try to write some daily coverage. Now lets see if I can get to sleep…

Update: The meeting actually takes place in Mykolayiv, 120km from Odessa :) Thank god that I will be picked up at the airport and don’t have to find it myself…

» Building KDevplatform, KDevelop and the PHP plugin from Git

Fri, 03/06/2009 - 01:21

In a follow up to my last post about the PHP plugin for KDevelop and Quanta I want to detail how I setup my build environment. Since I’m only working on KDevelop I only want to compile that. For all other applications, I use the packages my distribution makes available. Below you this is possible.

Note: I use Kubuntu and hence some commands like aptitude and the package names etc. will have to be adapted to your specific distribution. But the general idea should be the same and the packages should be called at least somewhat similar. You could always take a look at the techbase article on compilation of KDE 4 to get a more general HowTo.

It is generally a very good idea to read some articles on the techbase. Especially in the Getting Started section.

getting the dependencies

First, you’ll need to install some packages to satisfy dependencies and to get a working compile chain (think cmake, gcc and stuff). The following command only lists very few packages but they have a huge list of dependencies which your package manager will take into account automatically. Don’t be suprised by a possibly huge list of packages ;-) So some disk space will be required (though I doubt it’s more than 250MB in total).

Note: You’ll need the KDE 4.2.x versions of the KDE libraries and development packages. When you use Kubuntu, you can follow this article to get up to date packages for the 8.10 release.

  1. # I hope these are all, it's been a time since I did that the last time
  2. # please report if anything is missing
  3. aptitude install kdelibs5-dev kdebase-workspace-dev \
  4. libqt4-dev build-essential subversion kdesdk-scripts \
  5. bison flex
removing old cruft

To prevent binary compatibility issues that will result in crashes, you have to remove all KDevelop & KDevplatform packages provided by your package maintainer. In karmic it should be enough to remove kdevplatform, and it will remove all dependent packages:

  1. aptitude purge kdevplatform libsublime
setting up your environment

Inspired by the techbase article on improved productivity in KDE4, particularly the bashrc listed there, I’ve come up with the following way to configure my system:

First visit my shell helper git repo on GitHub and download the two files kde4_setup_build_environment.sh and bash_setup_kde4_programming.

set the environment variables

Move the file kde4_setup_build_environment.sh to ~/.kde/env and make it executable. You might want to adapt the paths for the variables KDE_BUILD, KDE_SRC and KDEDIR inside that file to your likings.

This part is required to make sure that compiled programs will act just like normal programs installed globally (e.g. with your package manager) right from the start of your KDE session. I.e. KRunner works fine and custom plugins are found etc.

make your life easier with some bash magic

Now alter your ~/.bashrc and to the bottom of that file add the following line:

  1. . ~/.bash_setup_kde4_programming

NOTE: This assumes that you saved the afore mentioned bash_setup_kde4_programming file to ~/.bash_setup_kde4_programming. You might have to change the path.

NOTE: That file also sources the above script to set the environment variables. I’m not sure it’s required, but it doesn’t hurt. So make sure the path is correct there.

Now to the fun part

Once all that’s done, you have to log out of your bash session to get the environments. Maybe even logout of your KDE session to make it aware of the new paths as well.

checking out KDevplatform, KDevelop and the PHP plugin

Get the latest and greatest directly from Git Master (see also git.kde.org Manual on techbase). But first make sure you setup the Git URL prefixes, by putting the following into your ~/.gitconfig file:

  1. [url "git://anongit.kde.org/"]
  2. insteadOf = kde:
  3. [url "git@git.kde.org:"]
  4. pushInsteadOf = kde:

Now checkout the sources:

  1. cs # cs is not a typo! see above
  2. git clone kde:kdevplatform
  3. git clone kde:kdevelop
  4. # if you only want KDevelop, you can stop here. The rest is for PHP
  5. git clone kde:kdevelop-pg-qt
  6. git clone kde:kdev-php
  7. git clone kde:kdev-php-docs
compiling and installing

Now it’s time to compile all that code you just checked out. Hopefully you got all required dependencies. If you need all bells and whistles, you’ll have to install some more packages I’m sure. If you run the code below, take a good look at the output of the cmakekde command (especially at the beginning). It lists not-found dependencies.

Note: cmakekde is supposed to be run from inside your source folder (e.g. cs $FOLDER; cmakekde).

  1. for p in kdevplatform kdevelop kdevelop-pg-qt php php-docs; do
  2. cs $p
  3. cmakekde
  4. done;
  5. kbuildsycoca4 # make sure new plugins etc. are found

Pretty easy, hum? Let’s hope everything worked fine :)

staying up to date

That above command is only required once. Everytime after that, you can simply do the following which will make sure you are running the latest and greatest:

  1. for p in kdevplatform kdevelop kdevelop-pg-qt php php-docs; do
  2. cs $p
  3. git pull --rebase && make install
  4. done
The End

Hope I have not forgotten anything and that this (rather lengthy…) HowTo is of some help to a few of you out there. Looking forward to feature requests, bug reports etc.

UPDATE 30/03/11: updated to git.kde.org location

UPDATE 18/05/10: updated to include kdevelop-pg-qt, introduced for loops in setup snippets

UPDATE 07/05/10: updated to git locations

UPDATE 08/01/10: updated to extragear location of php & php-docs

UPDATE 01/12/09: added php-docs, updated to extragear location of kdevplatform & kdevelop.

UPDATE 17/12/09: updated to kdereview location of php & php-docs

» PHP support for KDevelop 4 (and eventually Quanta+)

Tue, 03/03/2009 - 00:28

Hello Planet KDE!

I want to give you a little insight on the current state of PHP support in KDevelop4:

Me and Nikolaus Sams (nsams) are working diligently on a plugin for PHP support in playground. It’s somewhat stable, i.e. we fix any crashes we stumble upon, but I would call it Alpha state at most. It may eat your babies so to speak. Yet I’m happy to say that at least one user is already using it for production (hi leinir ;-) ).

implemented PHP support

Well, here’s a (not complete) list of features that are already working. Though I have to warn you: no screenshots included ;-) It’s actually all very similar to the C++ screenies you can see on the web.

sematic highlighting

Let’s start with a feature that only very recently was added for PHP - semantic highlighting. Niko moved some language independent parts of the C++ plugin from KDevelop to KDevplatform and now PHP has the same code highlighting features as C++.

I personally love this feature since it makes it even easier to grasp code and it makes the code highlighting more consistent since there is no visual difference between PHP built-in functions/constants and your own.

code completion

Arguably one of the most useful features the DUChain enables us to write is code completion. There’s already full support for:

  • PHP built-in functions, classes, constants, superglobals
  • user-defined functions, classes, constants, superglobals, variables, etc.
  • proper code completion for objects which respects access modifiers (private, public, protected) and differentiates between static/non-static members and methods
  • code completion for overridable and implementable functions inside classes
  • hints in the argument list of function- and method class
  • sane code completion after keywords such as “extends, implements, catch(), new, throw” and some more I think

There’s still some bugs to fix and a few features to implement. But I can easily say that even the current state of code completion makes one wonder how he could use Quanta (from KDE3 times) for such a long time! It’s simply nothing compared to this!

The next feature I hope to add is support for type hinting in function calls. I.e. only show arrays where arrays are requested and the same for objects of a given type. Also no PHP keywords are currently completed at all

other DUChain/UseBuilder stuff

Thanks to the DUChain you already get lots of information about declarations, such as uses (which files, which lines etc.). Also very neat is the hover popup you might now from C++ which among others shows you phpdoc comments inside your browser. I also plan to integrate the php.net documentation into KDevelop, similar to what is already possible for QtHelp.

inline validation / syntax checking / linting

Another feature which saves lots of time is on-the-fly syntax checking: You won’t have to fire up your web-app inside a browser just to be greated by that pesty “syntax error, unexpected ‘CHAR’ in FILE on line XYZ” message… No! Instead you will see a nice reddish zig-zag line where you made the error and can fix it before heading off to the browser.

But we don’t only do basic syntax checking. We do more than that, thanks again to the power of the (holy?) DUChain. You can spot undeclared variables, function/method/class/constant redeclarations and more. Actually I hope that one day we spot most of the notices, warnings and errors PHP could emit.

tests

We already have a multitude of regression tests which will make sure that we don’t mess up any existing stuff. Lets hope for even more of them :) I love test-driven development.

The End

Well, thats pretty much it for the moment. You can have a look at what we are up to at the Quanta Feature plan on techbase.

If you are a PHP developer and can write C++ with Qt, why not get in touch with us? You can find us both on the KDevelop mailinglist and at least me and leinir are often found in #kdevelop on freenode.

PS:

Let me finish with a quick introduction of myself:

My name is Milian Wolff, I study Physics at the FU Berlin (just finished the 3rd semester). I started learning programming when I was around 14 with PHP. Over the years I became very good in it and the other webdevelopment techniques like Css, JavaScript etc. Recently I started to fullfill my biggest geek dream by learning C++/Qt/KDE and starting to contribute to the KDE project.

Some of you might now my from the LinuxTag in Berlin where I could be found at the Kubuntu-De.org community booth. At least with some of you I had a beer (well, I doubt it was only one). I hope to repeat this tradition in 2009. Every once in a while I can also be spotted at ubuntu-berlin events.

» Take 2: Download script for springerlink.com Ebooks

Tue, 02/24/2009 - 22:58

NOTE: This script is apparently against the licensing contract between universities and Springer, see: http://www.bib.hm.edu/aktuelles/news/newsdetail_9984.de.html

NOTE 2: I do not maintain this script anymore. Please look for an alternative.

Seems like quite some people are interested in my bash script for downloading ebooks from http://springerlink.com.

That script has some quirks, the greatest of all that it was written in bash which makes it kind of hard to implement new features. And one which was requested was support for books which span multiple pages on SpringerLink.

So here I present springer_download.py - a Python rewrite which should handle all the old links and some more. This is the very first program I’ve written in Python. And since it has to run on the Zedat servers it’s limited to Python 2.4.x without any fancy shmancy additions (a pity, since I’d love to use urlgrabber or pycurl).

the script

You can find the sources on GitHub: http://milianw.github.com/springer_download/

I plan to put all my future code snippets in public repositories on GitHub. That way you can easily track changes and stay up to date. GitHub also has a nice “download” feature which you can use to get the current version. You can find my profile and my repositories at http://github.com/milianw

Note: This script is intended to be run under Linux or other *nix’es which fulfill the requirements (Python 2.4.x, iconv and pdftk). Windows is not supported.

TODO
  • introduce multithreading for faster / simultaneous downloads
  • add speed to progressbar
  • use progressbar in source-downloader
  • use one git-repo per project (makes links work properly)

» Kate linter plugin

Thu, 01/15/2009 - 18:58

Just a quicky: I wrote a little plugin for KTextEditor which supplies you with basic error checking when you save documents. Currently only PHP (via php -l) and JavaScript (via JavaScript Lint) are supported.

» profile.class.php

Tue, 06/24/2008 - 18:29

Every now and then I want to profile a given part of PHP code. For example I want to quickly check wether my current changeset to GeSHi works faster or is horribly slower. For a big change I’ll stick to Xdebug and KCachegrind. But for a quick overview? Overkill in my eyes.

Say hello to profile.class.php, a simple timer class for PHP5 which you can use to get an overview about where how much time is spent. This is in no way a scientific method nor should you take the results of a single run as a basis for you decisions.

I’ve set an emphasize on an easy API so you don’t have to pollute your code with arbitrary hoops and whistles.

UPDATE: You can find the current updated source in the SVN repo of GeSHi.

» recent GeSHi contributions (apache, xorg, apt, performance, ...)

Wed, 06/18/2008 - 22:46

Your favourite syntax highlighter for web applications, GeSHi, recently got some new features and bug fixes. By yours sincerely. A rough summary of what I contributed:

  • various performance improvements, i.e. some speed optimizations and reduced memory consumptions (especially peak memory usage is down by roughly 1MB when highlighting geshi.php by itself)
  • minor bugfixes, including one which prevents some nasty PHP notices on PHP 5 systems to contaminate your precious log files
  • improved language files: bash, apache
  • added language files: GNU Gettext, Xorg configuration and Apt sources.list

Some of those features were already shipped with the recent 1.0.7.22 release. But the two new language files and the improvements to the existing apache language file are currently only available via SVN. Wait for the next stable release which should be 1.0.8.

To see two pretty examples, read on after the break: