This week I received notice that my proposal for a presentation at the J-Fall 2009 was accepted. So on the 11th of November I will be discussing what a 5-star system is and how to get it. For those of you who cannot wait to find out what it means to get stars for your system can take a quick look over here.
The full abstract of the presentation can be found here (in Dutch). If you want to attend you should register yourself over here.
Hope to see you in Bussum!
Showing posts with label Me. Show all posts
Showing posts with label Me. Show all posts
Finish what you start ....
When I was young, my mother used to tell me that I should first finish what I started before moving to something new. I think this was mostly because in order to finish something I had to clean up the mess I made, but it's not a really bad rule to keep in mind I guess. However, even though I should first finish all my other projects before moving on, I picked up another project last week: getting a PhD.
Yep, as of the first of October my boss allows me to spend two days a week on doing research. This research is going to be (how surprisingly) in the field of static analysis and software quality. Our first research-topic is already starting to shape itself and I believe (how surprisingly) that it is going to lead to interesting results.
It might be nice to perform research, but in order to get a PhD you cannot get far without 1) good focus and 2) good supervisors. Luckily, I have a team of two supervisors that can certainly keep me focused: Joost Visser and Arie van Deursen.
In order to keep everybody up-to-date with the progress of the research, and to spend a little time in a more research-oriented environment, I will be traveling to Delft once a week. While last week was mostly filled with arranging a workspace, this week is going to be filled with giving a talk at the Research Colloquium. So if you have not heard my Fluent Interfaces talk yet, this is probably your last chance :)
Yep, as of the first of October my boss allows me to spend two days a week on doing research. This research is going to be (how surprisingly) in the field of static analysis and software quality. Our first research-topic is already starting to shape itself and I believe (how surprisingly) that it is going to lead to interesting results.
It might be nice to perform research, but in order to get a PhD you cannot get far without 1) good focus and 2) good supervisors. Luckily, I have a team of two supervisors that can certainly keep me focused: Joost Visser and Arie van Deursen.
In order to keep everybody up-to-date with the progress of the research, and to spend a little time in a more research-oriented environment, I will be traveling to Delft once a week. While last week was mostly filled with arranging a workspace, this week is going to be filled with giving a talk at the Research Colloquium. So if you have not heard my Fluent Interfaces talk yet, this is probably your last chance :)
A Java-Summercamp
It has been a while , but on the 29th of August I have attended the 2008 version of the Java Summercamp. This gathering was organized by profict, a dutch IT-company. They have an office with a great view (picture), now that is what I call a green working environment!
The topic of this day was Domain Specific Languages (DSL's). Since my talk about fluent interfaces at the J-Spring 2008 I became more and more interested in this topic. I hoped to hear more about why you would want to use a DSL, and see some examples of DSL's in practice. Luckily, I got what I wanted.
The first speaker was Neal Ford. His first presentation (slides) gave a general overview of the usefulness of DSL's. He argued that Java can be seen as a framework-oriented language. Nowadays, a Java-programmer uses many frameworks which he ties together with configuration-files written in XML. He proposes to use a DSL to abstract over these large configuration files in order to make it easier to tie frameworks together. He also gave an overview of some techniques to implement (mostly internal) DSL's. Actually, his second presentation mostly consisted of examples of DSL's in various languages. It is always fun to see examples of what you can do in other languages.
Sven Efftinge was the second speaker with his presentation (slides) about XText. I was surprised to see that it actually looked very simple to 1) create a DSL by typing in EBNF 2) generate an eclipse editor for this DSL with the click of a button and 3) generate a generator for your DSL using the same click. Naturally, everything was already set-up so that it looked easier then it actually is. I have tried to make a small example to show at the office, but failed miserably to get the generator to do what I want. Anyhow, if you have a spare afternoon then checking out this project is certainly worth the effort.
The third (and last) speaker was Zef Hemel. His presentation (slides) about WebDsl gave a nice overview of the setup and current status of the project. I was already a bit familiar with the project and it was fun to get an update. Also, I enjoy seeing the face of people that are confronted with Stratego for the first time :)
All and all I can say that it certainly an afternoon well spent.
The topic of this day was Domain Specific Languages (DSL's). Since my talk about fluent interfaces at the J-Spring 2008 I became more and more interested in this topic. I hoped to hear more about why you would want to use a DSL, and see some examples of DSL's in practice. Luckily, I got what I wanted.
The first speaker was Neal Ford. His first presentation (slides) gave a general overview of the usefulness of DSL's. He argued that Java can be seen as a framework-oriented language. Nowadays, a Java-programmer uses many frameworks which he ties together with configuration-files written in XML. He proposes to use a DSL to abstract over these large configuration files in order to make it easier to tie frameworks together. He also gave an overview of some techniques to implement (mostly internal) DSL's. Actually, his second presentation mostly consisted of examples of DSL's in various languages. It is always fun to see examples of what you can do in other languages.
Sven Efftinge was the second speaker with his presentation (slides) about XText. I was surprised to see that it actually looked very simple to 1) create a DSL by typing in EBNF 2) generate an eclipse editor for this DSL with the click of a button and 3) generate a generator for your DSL using the same click. Naturally, everything was already set-up so that it looked easier then it actually is. I have tried to make a small example to show at the office, but failed miserably to get the generator to do what I want. Anyhow, if you have a spare afternoon then checking out this project is certainly worth the effort.
The third (and last) speaker was Zef Hemel. His presentation (slides) about WebDsl gave a nice overview of the setup and current status of the project. I was already a bit familiar with the project and it was fun to get an update. Also, I enjoy seeing the face of people that are confronted with Stratego for the first time :)
All and all I can say that it certainly an afternoon well spent.
Is he back?
It has been eight months since my last post to this blog. Also, the release plan did not work out as well as I had hoped. So what did I do in the intermediate months?
Well, I ended last year by buying me a 'real' house instead of renting an apartment. For us it is pretty large, currently even the cats have an own room, but this will probably change over time. Buying a house really helps you to spend your time since there is all sorts of paperwork to fill out, people to inform and things to pack. We moved in at the end of March and I think that we are currently at the point that every company we deal with knows that we had a change of address. The next objective is to unpack and store away everything that we moved. There are still some (closed) boxes standing around here and there.
During the time that we where preparing to move to our new house my (at that time) girlfriend and I where also organizing a very important event: our wedding. That is right, on April the 26th we got married! It was a wonderful day in which we did the things that we enjoy together with our friends and family. We got married, went to a movie and had a party at the home of our Scouts. Maybe not the most traditional wedding ever, but certainly one that we enjoyed!
Even during the buying of a house and the planning of a wedding one must keep on working, so I did. I learned a lot about how to do agile programming, how one can quantify the quality of software and how to be (even more) pragmatic.
Apart from the 'normal' work, me and one of my colleagues wrote a paper called Multidimensional Software Monitoring Applied to ERP. This paper is accepted at the SQM 2008. It was very nice to attend a conference as the author of a paper, certainly when the conference is held in Athens :)
Next to this paper, I also gave a talk at the J-Spring 2008, This talk, titled Putting Fluent Interfaces to the test, was about designing and using a Fluent Interface. If you are not familiar with this style of API-design be sure to follow the link.
So I bought a house, got married and enjoy the work that I do. I guess you van say I am really settling into society ;)
Unfortunately, this settling in has taken so much energy from me that I did not find the time to work on PHP-Sat. However, since I have found the time and energy to write this post, I should also be able to find some for the PHP-Sat-project again!
Well, I ended last year by buying me a 'real' house instead of renting an apartment. For us it is pretty large, currently even the cats have an own room, but this will probably change over time. Buying a house really helps you to spend your time since there is all sorts of paperwork to fill out, people to inform and things to pack. We moved in at the end of March and I think that we are currently at the point that every company we deal with knows that we had a change of address. The next objective is to unpack and store away everything that we moved. There are still some (closed) boxes standing around here and there.
During the time that we where preparing to move to our new house my (at that time) girlfriend and I where also organizing a very important event: our wedding. That is right, on April the 26th we got married! It was a wonderful day in which we did the things that we enjoy together with our friends and family. We got married, went to a movie and had a party at the home of our Scouts. Maybe not the most traditional wedding ever, but certainly one that we enjoyed!
Even during the buying of a house and the planning of a wedding one must keep on working, so I did. I learned a lot about how to do agile programming, how one can quantify the quality of software and how to be (even more) pragmatic.
Apart from the 'normal' work, me and one of my colleagues wrote a paper called Multidimensional Software Monitoring Applied to ERP. This paper is accepted at the SQM 2008. It was very nice to attend a conference as the author of a paper, certainly when the conference is held in Athens :)
Next to this paper, I also gave a talk at the J-Spring 2008, This talk, titled Putting Fluent Interfaces to the test, was about designing and using a Fluent Interface. If you are not familiar with this style of API-design be sure to follow the link.
So I bought a house, got married and enjoy the work that I do. I guess you van say I am really settling into society ;)
Unfortunately, this settling in has taken so much energy from me that I did not find the time to work on PHP-Sat. However, since I have found the time and energy to write this post, I should also be able to find some for the PHP-Sat-project again!
So much interesting to read ...
... and less time to do it!
Since I started my full-time job I noticed that it is a lot harder to stay up to date with all the latest (online) developments. During the writing of my thesis I had a considerable amount of time which I could spend on reading blogs and news-items, and following mailing-lists. When you spend most of your day actually working you learn to prioritize which things you want to read :)
One of the things I did managed to read, albeit a bit late, is this thread on the PHP.internals list written by Wietse Venema. It is a follow-up on this thread in which a first proposal was made to integrate a perl-style taint-mode into the core of PHP. The results posted in the follow-up thread look promising. It is also interesting to see that he has gone from a black-and-white taint-mode, to a more leveled approach. Currently the proposal only contains a subset of the levels available in PHP-Sat, but I think that the most fundamental ones are definitely there.
Even though Wietse is developing a prototype I think he will have a hard time getting this taint-mode into the actual core of PHP. Within both threads the general opinion seems to be that the idea is nice, but the developers of PHP seem to think of many situations in which it could fail. I hope to see more results of this idea soon!
Going over some other interesting threads in the internals-list I found a reference to a tool called PHPLint. (Isn't is funny to see that there are all sorts of initiatives popping up that that try to make PHP more secure/stricter). I haven't have time to take a better look at this tool, but a first glance definitely showed potential. I'll try to examine this tool more thoroughly at the end of this week.
While there is less time to read on-line material, there is more time to read off-line stuff. Since I am using public transportation to get to work I have an extra hour a day to read actual books and publications. One of the books I have read in the past few weeks is a printed version of "Producing Open Source Software" (ProducingOss) written by Karl Fogel. My conclusion: absolutely worth reading!
ProducingOss contains all sorts of tips, hints and best practices. Even if you are not involved in an open source project it is still useful to read. Almost everything in the book can also be applied to closed-source projects. Furthermore, it contains many pointers to other interesting literature. One of these pointers lead me to The Cathedral and the Bazaar, my current read-while-traveling-to-and-from-work book.
I intend to use several things from ProducingOSS within PHP-Sat. I will just have to think about how I can fit the project in my current schedule, but it will definitely be fitted in.
Since I started my full-time job I noticed that it is a lot harder to stay up to date with all the latest (online) developments. During the writing of my thesis I had a considerable amount of time which I could spend on reading blogs and news-items, and following mailing-lists. When you spend most of your day actually working you learn to prioritize which things you want to read :)
One of the things I did managed to read, albeit a bit late, is this thread on the PHP.internals list written by Wietse Venema. It is a follow-up on this thread in which a first proposal was made to integrate a perl-style taint-mode into the core of PHP. The results posted in the follow-up thread look promising. It is also interesting to see that he has gone from a black-and-white taint-mode, to a more leveled approach. Currently the proposal only contains a subset of the levels available in PHP-Sat, but I think that the most fundamental ones are definitely there.
Even though Wietse is developing a prototype I think he will have a hard time getting this taint-mode into the actual core of PHP. Within both threads the general opinion seems to be that the idea is nice, but the developers of PHP seem to think of many situations in which it could fail. I hope to see more results of this idea soon!
Going over some other interesting threads in the internals-list I found a reference to a tool called PHPLint. (Isn't is funny to see that there are all sorts of initiatives popping up that that try to make PHP more secure/stricter). I haven't have time to take a better look at this tool, but a first glance definitely showed potential. I'll try to examine this tool more thoroughly at the end of this week.
While there is less time to read on-line material, there is more time to read off-line stuff. Since I am using public transportation to get to work I have an extra hour a day to read actual books and publications. One of the books I have read in the past few weeks is a printed version of "Producing Open Source Software" (ProducingOss) written by Karl Fogel. My conclusion: absolutely worth reading!
ProducingOss contains all sorts of tips, hints and best practices. Even if you are not involved in an open source project it is still useful to read. Almost everything in the book can also be applied to closed-source projects. Furthermore, it contains many pointers to other interesting literature. One of these pointers lead me to The Cathedral and the Bazaar, my current read-while-traveling-to-and-from-work book.
I intend to use several things from ProducingOSS within PHP-Sat. I will just have to think about how I can fit the project in my current schedule, but it will definitely be fitted in.
Attending J-Fall 2007
This Thursday (October 10th) I was lucky enough to get a ticket (and approval) to go the J-Fall conference organized by the NL-jug. My conference day started when I met some colleagues at the train-station to travel to Bussum-zuid. Within this nice-looking town the J-Fall found its home in 't Spant, a professional conference-facility.
The keynote of the conference was given by the "Sun Java Technology Outreach Team", which is basically a group of four engineers that talk about what you can do with Java. The keynote started with a nice overview of the different technologies Sun is working on. After this, a demo of JavaFX was given. Chuck Munn-Lee showed how easy JavaFX makes it to create a circle that morphs into a rectangle when you click on it. I also liked the fact that his editor did not only support code-completion, but also 'Color-completion'. Unfortunately, the other demos were are a bit disappointing because of several technical problems.
The first 'real' talk I attended was called From Java to Ruby … and Back. The speaker provided lots of material on the slides which made them a little bit overwhelming. Fortunately, he assured us that the slides would also be distributed digitally. The contents of the presentation was an introduction to Ruby and a comparison with Java. One of the conclusions was that the speaker would happily code 80 percent of his applications in Ruby instead of Java. Quit a statement on a conference promoting the use of Java :)
The second talk I visited was about JUnit, or actually JUnit 4. I was a little bit disappointed by this presentation because all of the content was already discussed in an article printed in the last issue of the Java magazine. Furthermore, the pace of the presentation was terribly slow, which made it hard to focus. The only interesting bit of information I extracted was that JUnit4 allows you to define parameterized tests, something I might have missed in the article.
After a little bite, a longer walk and a stroll along the companies on display it was time for the second keynote. This keynote was very slick, had nice graphics and a strong story. Three different people talked about what Adobe offered, which activities are done by Adobe for the open source community, and what we can expect from Adobe in the future. They even tried to answer the question why Adobe was sponsoring the J-Fall. The answer was probably not very clear because I cannot reproduce it. The talk basically felt like one long commercial for the Adobe company.
Right after the second keynote I went to the talk of Peter Hendriks about Eclipse Mylyn. I very much enjoyed this presentation. The story was clear without telling to much detail and the demo was well-prepared. Peter even turned on the magnifying glass in Windows to zoom in to the interesting parts of the demo. These are the kind of details that show that this presentation was well-prepared.
On to the contents, the Eclipse Mylyn plug-in has all kind of nice features that can help you focus on your task. For example, the file-list can be filtered to show only those files that you have edited during the current task. Also, I especially liked the fact that you can define a test-target that only runs the tests associated with the current task. If you use Eclipse you should definitely take the time to check this plug-in out!
After getting another cup of coffee I set down in front of the biggest stage to listen to Java-specialist Heinz Kabutz. He explained The Secrets of Concurrency using ten (humorously named) laws. Each of the laws had an explanation of the name, a link to the actual problem and a solution. The talk was relatively straight-forward which made it easy to follow. A perfect talk for the late afternoon!
The last talk I visited was about the new JSR-286 specification for portals and portlets. Although the announcement implicated that the talk was only about the specification we hoped for a dynamic talk. Unfortunately, we got what was announce. An overview of the current version of the spec, a small list of shortcomings and a larger list of new features. Even though I was interested in the topic it was hard to stay focussed during the complete talk. Especially when the volume of the music in the bar next-door was turned up.
As a conclusion I can say that, despite some of the less entertaining talk, I really enjoyed the day. It was interesting to hear about a lot of different topics, and fun to see different companies present themselves. If I get the change I will definitely attend the upcoming J-Spring conference.
The keynote of the conference was given by the "Sun Java Technology Outreach Team", which is basically a group of four engineers that talk about what you can do with Java. The keynote started with a nice overview of the different technologies Sun is working on. After this, a demo of JavaFX was given. Chuck Munn-Lee showed how easy JavaFX makes it to create a circle that morphs into a rectangle when you click on it. I also liked the fact that his editor did not only support code-completion, but also 'Color-completion'. Unfortunately, the other demos were are a bit disappointing because of several technical problems.
The first 'real' talk I attended was called From Java to Ruby … and Back. The speaker provided lots of material on the slides which made them a little bit overwhelming. Fortunately, he assured us that the slides would also be distributed digitally. The contents of the presentation was an introduction to Ruby and a comparison with Java. One of the conclusions was that the speaker would happily code 80 percent of his applications in Ruby instead of Java. Quit a statement on a conference promoting the use of Java :)
The second talk I visited was about JUnit, or actually JUnit 4. I was a little bit disappointed by this presentation because all of the content was already discussed in an article printed in the last issue of the Java magazine. Furthermore, the pace of the presentation was terribly slow, which made it hard to focus. The only interesting bit of information I extracted was that JUnit4 allows you to define parameterized tests, something I might have missed in the article.
After a little bite, a longer walk and a stroll along the companies on display it was time for the second keynote. This keynote was very slick, had nice graphics and a strong story. Three different people talked about what Adobe offered, which activities are done by Adobe for the open source community, and what we can expect from Adobe in the future. They even tried to answer the question why Adobe was sponsoring the J-Fall. The answer was probably not very clear because I cannot reproduce it. The talk basically felt like one long commercial for the Adobe company.
Right after the second keynote I went to the talk of Peter Hendriks about Eclipse Mylyn. I very much enjoyed this presentation. The story was clear without telling to much detail and the demo was well-prepared. Peter even turned on the magnifying glass in Windows to zoom in to the interesting parts of the demo. These are the kind of details that show that this presentation was well-prepared.
On to the contents, the Eclipse Mylyn plug-in has all kind of nice features that can help you focus on your task. For example, the file-list can be filtered to show only those files that you have edited during the current task. Also, I especially liked the fact that you can define a test-target that only runs the tests associated with the current task. If you use Eclipse you should definitely take the time to check this plug-in out!
After getting another cup of coffee I set down in front of the biggest stage to listen to Java-specialist Heinz Kabutz. He explained The Secrets of Concurrency using ten (humorously named) laws. Each of the laws had an explanation of the name, a link to the actual problem and a solution. The talk was relatively straight-forward which made it easy to follow. A perfect talk for the late afternoon!
The last talk I visited was about the new JSR-286 specification for portals and portlets. Although the announcement implicated that the talk was only about the specification we hoped for a dynamic talk. Unfortunately, we got what was announce. An overview of the current version of the spec, a small list of shortcomings and a larger list of new features. Even though I was interested in the topic it was hard to stay focussed during the complete talk. Especially when the volume of the music in the bar next-door was turned up.
As a conclusion I can say that, despite some of the less entertaining talk, I really enjoyed the day. It was interesting to hear about a lot of different topics, and fun to see different companies present themselves. If I get the change I will definitely attend the upcoming J-Spring conference.
My last words ...
... about my study that is!
After seven years of attending college I am no longer a student anymore. It still has to sink in a little bit, but I will probably get used to it very soon. It is quit confronting to transfer all of your (bank-)accounts to a non-student one :(
If you are interested in the final result of the thesis you can visit my thesis page, or just download the complete thesis here. The slides of my presentation can be found on this page. Even though the project is finished (in the sense that I am not obligated to work on it anymore) I am still interested in remarks and comments you might have.
In my opinion I already had some vacation the past couple of weeks. I finished the major part of my thesis at the end of August, so in September I only had to integrate comments from my supervisors. This gave me lots of spare time which I used to relax a little bit.
Therefore, I took some time to found a nice job. After visiting several companies I decided to accept a job at the Software Improvement Group. During the interviews I got the feeling that this is a challenging job where I can learn a lot. Whether this feeling is correct is something that only time can tell us.
I will just wait and see what happens Monday morning!
After seven years of attending college I am no longer a student anymore. It still has to sink in a little bit, but I will probably get used to it very soon. It is quit confronting to transfer all of your (bank-)accounts to a non-student one :(
Thesis
I defended my thesis yesterday morning in front of a crowded room. Although I was a bit nervous before the talk this feeling faded away when I started the presentation. I thought it went reasonably well and this was confirmed by my supervisor(s). Please allow me to thank Johan Jeuring and Jurriaan Hage for their time and effort to supervise me.If you are interested in the final result of the thesis you can visit my thesis page, or just download the complete thesis here. The slides of my presentation can be found on this page. Even though the project is finished (in the sense that I am not obligated to work on it anymore) I am still interested in remarks and comments you might have.
Work
And what do people usually do when they graduate college? Right, they take a vacation!In my opinion I already had some vacation the past couple of weeks. I finished the major part of my thesis at the end of August, so in September I only had to integrate comments from my supervisors. This gave me lots of spare time which I used to relax a little bit.
Therefore, I took some time to found a nice job. After visiting several companies I decided to accept a job at the Software Improvement Group. During the interviews I got the feeling that this is a challenging job where I can learn a lot. Whether this feeling is correct is something that only time can tell us.
I will just wait and see what happens Monday morning!
Experiencing a World Jamboree
It has been one month since the last blog post. The reason for this is that I have traveled to England to (finally) attend the World Scout Jamboree. Describing everything that happened in the past weeks does not only result in an overly long post, it is also a bit boring. On the other hand, only giving the facts is also boring. Therefore, let us just scan through the trip and talk about the more interesting highlights.
The opening ceremony was to be held in the evening, around 8pm. This was changed once, twice and again because of a special agenda that needed to be respected. It turned out that Prince William himself was attending the opening ceremony. Our places in the arena give us a change of seeing him close by and even hitting him on the head, although nobody thought that would be wise.
Don't get me wrong, the majority of the activities were fun and exciting. Our participants and the staff had a great time! Everyone just expected the English organization to be more organized.
All there is left to say is that I had a great time at the Jamboree. Hopefully I will be able to join the 22nd World Jamboree in Sweden in 2011. Now lets get back to actually making sure I can actually graduate in October 2007 :)
Pre Jamboree Tour
Our trip started with a pre-jamboree tour organized by the our Contingent staff. We camped on Kibblestone, a reasonably big camp-site in England. Getting there involved two buses, a baggage-lorry and a boat. All the luggage of our troup, consisting of 40 persons, had to go with us on each of these vehicles. The boat was easy, but getting everything into the other three was a bit of a challenge. However, everything arrived safe and sound around 2 AM in the morning. After putting up the tents everybody slept like a baby.The wheather
The first day of our stay in Kibblestone was accompanied by lots of sunshine. During my first meeting there where already complaints that some of the female participants had to put on more clothing when they walked around. Luckily for the complainer, this was forced down upon us by the weather-gods. It did not rain all the time, but it rain enough to turn the grass, the roads and the toilets into a big mud-pit. During the jamboree itself it was common to pull an item out of its storage place and see the original Kibblestone-mud still sitting on it. It was just everywhere!Activities
The weather also influenced the activities we did. Most of the activities could also be done in the rain, in between two showers or indoors. Most of the participants enjoyed the numerous excursions, sport games (of all kinds) and campfires. For some of the participants the visit to Stratford-upon-Avon was a good excuse to buy all sorts of goods, including the new Harry Potter. Unfortunately for them they had to wait to get it because the first event in this town was a visit to the shakespearience. However, upon arriving in the right street it was quit clear that we would not be entering the theater. Between us and the theater was not the expected road, but a small river of about 30 centimeters deep. More time to shop, more time to start with Harry Potter!Home Hospitality
An even more relaxing and special activity in the pre-jamboree tour was the home hospitality. The original concept was that each duo in our troop would stay with a family for two days. This was canceled by the English organization because there was a shortage of families that would host our scouts. Luckily, there where several scout-troops that wanted to host complete troops! After traveling for about six hours we arrived in Cardigan, a small city on the coast of Wales. We stayed wit the "3rd Cardigan Sea Scouts", a great group of people that terribly spoiled us. Our stay was a bit at the end of our pre-jamboree tour and the scouts of Cardigan made sure that we got our well-needed rest before we headed off to the real Jamboree. I cannot thank them enough for this fantastic time!Surprising News?
On the last day of the pre-jamboree tour I finally spoiled a game that a part of our Contingent staff was playing for over a week. Each day, my girlfriend got one or two letters that together would form a sentence. Several people tried to work it out, but they all failed before I finally showed the answer to my girlfriend. For those of you that are curious, please visit the news-site of our troop on the 26th of July.World Jamboree
It took a while before we left Kibblestone, one of the buses broke down after loading, but everybody of the Dutch contingent was on their way to the Jamboree. Some of the participants thought that there were a lot of people on Kibblestone (roughly 1350), they had not seen the Jamboree site yet. After only 3 hours on the bus we got out in the main bus terminal, only a short 20 minute walk from our campsite. I was told that many of our participants finally understood that taking to much luggage can really, really hurt your back.Opening Ceremony
Even though the 20 minute walk showed a little bit of the size of the Jamboree, the opening ceremony did the rest. After 3,5 hours everybody was assembled into the arena, roughly 40.000 scouts from over 150 countries. During the opening ceremony, every country was welcomed by both a real and a digital flag. One can imagine that it took a while before every country was named.The opening ceremony was to be held in the evening, around 8pm. This was changed once, twice and again because of a special agenda that needed to be respected. It turned out that Prince William himself was attending the opening ceremony. Our places in the arena give us a change of seeing him close by and even hitting him on the head, although nobody thought that would be wise.
Organization
Speaking of being wise, it was a good habit to pack as much as possible for a complete day. Walking to the other end of the campsite took about 45 minutes, that is without any chitchat-time. Furthermore, it could take some time to get you your food, a place to shower or a place on the bus. The shortest waiting time for a seat in the bus was about one hour, but it was not uncommon to wait for two or more. This showed that the English organization is pretty good in PR, everything was said to be completely organized, but not so good in actually making things happen. I still have to get a staff handbook which explains rules, procedures and activities for the Jamboree, something that could have been arranged a few months back. Furthermore, some of the activities themselves could have been prepared better. Sometimes even the people in charge of the activity did not know how things should be done.Don't get me wrong, the majority of the activities were fun and exciting. Our participants and the staff had a great time! Everyone just expected the English organization to be more organized.
Scouting Sunrise
One of the biggest events during this World Jamboree was the Sunrise ceremony, held on the exact moment that the Scouts movement turned 100 years old. During the opening (and closing) ceremony the arena was filled with all sorts of different flags, during this ceremony everyone had the same Purple Scouts flag. Even though the ceremony was a bit too religious for my taste, I enjoyed the ceremony very much. Especially the moment that everybody was trying to collect 100 signatures on their sunrise scarf, 40.000 people wanting each others autograph is kind of cool to see. The rest of the day was filled with the food festival, each country on the sub camp prepared a dish typically for its country, sharing this with other countries. It was very nice to see so many cultures sharing their own ideas and rituals. This was truly one of the highlights of the Jamboree.Departure
You might expect that the departure wasn't that well organized, but would you believe that the English organization began to think about the departure 3 days before the event ended? All of the previous arrangements with the Dutch Contingent where suspended which resulted in a rather huge challenge. In the original scenario we could stay on the Jamboree site until Thursday and Friday, but this was not possible anymore. After long debates ans short nights our Contingent staff provided a solution that was workable. The first group, including me, departed from the site on Wednesday to London for an excursion and from there to Essex University to sleep. It was very nice to sleep in a real bed and have access to your own shower! The next morning we started traveling around 6.00AM, I was home 14 hours later. The second group first had to relocate to a single spot on the Jamboree site after which they had a day of active excursions. They slept one more night on the Jamboree site and then had the same program as the first group.Conclusion
I have not yet begun to tell everything that happened on the Jamboree. For more information about our contingent you can visit http://www.wj2007.scouting.nl/, for more information about the activities of the Jamboree you can visit http://eng.thejamboree.org/ when it is back up.All there is left to say is that I had a great time at the Jamboree. Hopefully I will be able to join the 22nd World Jamboree in Sweden in 2011. Now lets get back to actually making sure I can actually graduate in October 2007 :)
Testing a contest
Wow, that was a rather interesting experience. I spend the last three days on testing the ICFP-contest. There is not much I can say about the actual content of the contest, but I can say that I learned several new things. Some of them are not so funny, while others are very cool!
Anyway, lets just say that our solution was not exactly optimal :) I am sure that other will do better. So if you have not done so, register here.
Have fun and hack away.
Anyway, lets just say that our solution was not exactly optimal :) I am sure that other will do better. So if you have not done so, register here.
Have fun and hack away.
A scouts week
Those of you that (try to) read the posts of this blog every week might have noticed the two-week gap between this post and the previous one. This gap originates from the hobby I practice since I was a (very) little boy: Scouting. Within the past week I had the chance to go to two camps, with a three-day rest-period in between. This results in a large amount of dirty clothes, little sleep, a voice like a grinder and lots and lots of fun!
The first camp I attended was the 'clusterweekend' of the Dutch Contingent. My role in this camp was that of quartermaster of the Bontbekplevieren, one of the 25 troops visiting the World Jamboree this summer. Because it is almost impossible to get all of the Dutch participants together on one terrain, the 25 troops where divided into three clusters. There where eight troops in our cluster, each troop consisting of 40 persons. Adding a few people for camping staff, working staff and general staff we had about 350 people attending this camp.
Even though the weather forecast was a bit disappointing at first, the rain all fell down on us during the first night. This immediately showed that our new tents are water-proof, which is a good thing considering the normal weather conditions on England. During the rest of the weekend we played some games on the beach, sorted out a massive amount of badges, played in a casino and had a big party. Luckily, the sun was shining on Sunday so we could pack everything in dry conditions. The weekend was a great success, and of course there are some general photo's, as well as photo's of our troop.
When I came home on Sunday I quickly unpacked everything and washed some of the clothes. I worked a bit on Monday and Tuesday, but I also had to take care of some things for Ontmoeting, the second camp of this week. Ontmoeting is organized once a year for all the scouts of our region in the age of 11-15. They are mixed into sub-camps to compete for the first place. Each year the competition is wrapped into a certain theme, this years theme was 'Bond maakt het Bond'. The mission was to become the replacement of James Bond. The 153 participants where divided into 6 camps, each representing a 'superhero' of some kind. I was part of the Bassie en Adriaan-camp, a rather famous duo in the Netherlands.
This camp started on Wednesday with the packing of 'Diana', the trailer of our group. After loading all sorts of stuff we want to the campsite which was relatively small, but this made the whole thing kind of cosy. On Wednesday-evening we had a BBQ and a campfire with the staff, the children arrived on Thursday morning. The next three days where filled with all sorts of larger games, smaller games and some pretty cool ticket-activities. Naturally, you can check these out on some of the photo's, made by the same people that also made the camp-news-paper. It is always hard to tell about the whole camp in just a few words, but it all boils down to having a lot of fun. This year the games where really fun, thank you 'spelstaf', and our sub-camp has won the cup! To quote a famous clown: 'Alles is voor Bassie!'
These kind of weeks are a great way to relax, no worries about making deadlines or missing important stuff. It is simply not possible to read a real news-paper, so you just ignore the rest of the world for a couple of days. Also, it gives me a lot of energy to start working again, so let's get to it!
After catching some more sleep of course...
The first camp I attended was the 'clusterweekend' of the Dutch Contingent. My role in this camp was that of quartermaster of the Bontbekplevieren, one of the 25 troops visiting the World Jamboree this summer. Because it is almost impossible to get all of the Dutch participants together on one terrain, the 25 troops where divided into three clusters. There where eight troops in our cluster, each troop consisting of 40 persons. Adding a few people for camping staff, working staff and general staff we had about 350 people attending this camp.
Even though the weather forecast was a bit disappointing at first, the rain all fell down on us during the first night. This immediately showed that our new tents are water-proof, which is a good thing considering the normal weather conditions on England. During the rest of the weekend we played some games on the beach, sorted out a massive amount of badges, played in a casino and had a big party. Luckily, the sun was shining on Sunday so we could pack everything in dry conditions. The weekend was a great success, and of course there are some general photo's, as well as photo's of our troop.
When I came home on Sunday I quickly unpacked everything and washed some of the clothes. I worked a bit on Monday and Tuesday, but I also had to take care of some things for Ontmoeting, the second camp of this week. Ontmoeting is organized once a year for all the scouts of our region in the age of 11-15. They are mixed into sub-camps to compete for the first place. Each year the competition is wrapped into a certain theme, this years theme was 'Bond maakt het Bond'. The mission was to become the replacement of James Bond. The 153 participants where divided into 6 camps, each representing a 'superhero' of some kind. I was part of the Bassie en Adriaan-camp, a rather famous duo in the Netherlands.
This camp started on Wednesday with the packing of 'Diana', the trailer of our group. After loading all sorts of stuff we want to the campsite which was relatively small, but this made the whole thing kind of cosy. On Wednesday-evening we had a BBQ and a campfire with the staff, the children arrived on Thursday morning. The next three days where filled with all sorts of larger games, smaller games and some pretty cool ticket-activities. Naturally, you can check these out on some of the photo's, made by the same people that also made the camp-news-paper. It is always hard to tell about the whole camp in just a few words, but it all boils down to having a lot of fun. This year the games where really fun, thank you 'spelstaf', and our sub-camp has won the cup! To quote a famous clown: 'Alles is voor Bassie!'
These kind of weeks are a great way to relax, no worries about making deadlines or missing important stuff. It is simply not possible to read a real news-paper, so you just ignore the rest of the world for a couple of days. Also, it gives me a lot of energy to start working again, so let's get to it!
After catching some more sleep of course...
Passing time
After I stopped working on the GUI for the RFG I have been working in Haskell again. It has been quite a while since I have worked with this language, so it takes me some time to get used to it again. Since it is a strongly typed language, as apposed to both Stratego and PHP, some things take longer to implement, but some mistakes are found by the type-checker. Unfortunately, this means that I have not done anything terribly interesting for my thesis.
So lets look at the other interesting project, PHP-Sat. I have been working on the integration of a second analysis within the constant-prorogation. This is coming along nicely, but it requires some heavy thinking and careful considerations. I have already worked my way up to the expression-level, so I hope to finish the rest of the constructs that were already supported by the end of this weekend.
In order to tell at least one interesting thing, and to not waste your time completely, I wanted to point out some interesting video-presentations. The first one is also the first one I ever saw through the internet: Drupal, Joomla! & GSoC. The title explains why I wanted to see it, and it is interesting for anyone that wants to know more about the GSoc from a projects point of view. The second also comes from the Google Tech Talks and is called How Open Source Projects Survive Poisonous People (And You Can Too). It is given by the people behind subversion and I especially liked the story about the bikeshed. The third presentation comes from Bram Molenaar, the creator of VIM (yes, that is the editor I mostly use). He talks about 7 Habits For Effective Text Editing, be sure to check it out even if you do not use VIM.
The presentations mentioned above are (some of) the presentations I have already seen, the following are on my todo-list. Please let me know if anyone of them is super-great, or a total waste of time.
So lets look at the other interesting project, PHP-Sat. I have been working on the integration of a second analysis within the constant-prorogation. This is coming along nicely, but it requires some heavy thinking and careful considerations. I have already worked my way up to the expression-level, so I hope to finish the rest of the constructs that were already supported by the end of this weekend.
In order to tell at least one interesting thing, and to not waste your time completely, I wanted to point out some interesting video-presentations. The first one is also the first one I ever saw through the internet: Drupal, Joomla! & GSoC. The title explains why I wanted to see it, and it is interesting for anyone that wants to know more about the GSoc from a projects point of view. The second also comes from the Google Tech Talks and is called How Open Source Projects Survive Poisonous People (And You Can Too). It is given by the people behind subversion and I especially liked the story about the bikeshed. The third presentation comes from Bram Molenaar, the creator of VIM (yes, that is the editor I mostly use). He talks about 7 Habits For Effective Text Editing, be sure to check it out even if you do not use VIM.
The presentations mentioned above are (some of) the presentations I have already seen, the following are on my todo-list. Please let me know if anyone of them is super-great, or a total waste of time.
- The paradox of choice
- Education in the Digital Age
- How to get paid to do open source (does this mention the GSoc?)
Thinking of Merging
I have been dealing with some challenges in the last couple of days. For example my practical assignment for DBA, to be implemented in MIL, and styling the GUI for my thesis, which is coming along just fine I guess. Both of these tasks are easy for people who invented/work with it every day, but I sometimes find it hard to wrap my mind around the problem or keeping track of every detail. Good luck for me there exists a topic where I can work on without repeatedly searching on Google, analyzing PHP!
Speaking of analyzing PHP, Martin has written a blog about the generation of rules for operator-precedence in PHP. He mentions some interesting ideas for work on grammar engineering, so if you are looking for a (thesis)-project you should definitely check it out. Otherwise it is just an interesting post to read.
As for my work in operators in PHP, I have finished the rest of the operators in PHP-Sat. Furthermore, the implementation of the constant-propagation regarding operators is revised within PHP-Front. This is done because I am thinking about merging the constant-propagation and the safety-type analysis into one big analysis. I know, it sounds like premature optimization (a.k.a. the root of all evil), but I can explain why it is necessary.
Consider the following piece of code:
Now lets look at the safety-type analysis. We first assign the safety-type IntegerType to the first two indexes of the array. The safety-type of $_GET['foo'] is then assigned to the third index of the array which is the parameter to echo in the last statement. We know that the safety-type is assigned to the third index because PHP-Sat keeps track of the internal index-count of arrays.
You might have noticed that both paragraphs are almost identical, except for the kind of value that is assigned. Thinking about this case, cases for function calls and cases for objects it turns out that performing the safety-analysis involves a lot of bookkeeping. This bookkeeping, for example the internal index-count, is not specific for the propagated values, it encodes the internal semantics of PHP. Therefore, in order to provide a good safety-type analysis, we have to embed this bookkeeping.
In order to avoid code duplication, which might be worse then premature optimization, I believe we must merge the two analyzes together. By separating the assignment of values from the bookkeeping we can visit a node, perform the bookkeeping and then perform as much analyzes on the node as we want. The only thing needed is a list of strategies that encodes a single analysis on the node.
The idea might sound a bit vague, but while I was working on the operators I already saw some duplication creeping in. Some of the strategies for both analysis only differ on the strategies to fetch or add some value, a perfect change to generalize a bit I would say.
Speaking of analyzing PHP, Martin has written a blog about the generation of rules for operator-precedence in PHP. He mentions some interesting ideas for work on grammar engineering, so if you are looking for a (thesis)-project you should definitely check it out. Otherwise it is just an interesting post to read.
As for my work in operators in PHP, I have finished the rest of the operators in PHP-Sat. Furthermore, the implementation of the constant-propagation regarding operators is revised within PHP-Front. This is done because I am thinking about merging the constant-propagation and the safety-type analysis into one big analysis. I know, it sounds like premature optimization (a.k.a. the root of all evil), but I can explain why it is necessary.
Consider the following piece of code:
$foo = array(1,2);When we consider the constant-propagation we first assign the values 1 and 2 to the first two indexes of the array. The value of $_GET['foo'] is then assigned to the third index of the array which is the parameter to echo in the last statement. We know that the value is assigned to the third index because PHP-Front keeps track of the internal index-count of arrays.
$foo[] = $_GET['bar'];
echo $foo[2];
Now lets look at the safety-type analysis. We first assign the safety-type IntegerType to the first two indexes of the array. The safety-type of $_GET['foo'] is then assigned to the third index of the array which is the parameter to echo in the last statement. We know that the safety-type is assigned to the third index because PHP-Sat keeps track of the internal index-count of arrays.
You might have noticed that both paragraphs are almost identical, except for the kind of value that is assigned. Thinking about this case, cases for function calls and cases for objects it turns out that performing the safety-analysis involves a lot of bookkeeping. This bookkeeping, for example the internal index-count, is not specific for the propagated values, it encodes the internal semantics of PHP. Therefore, in order to provide a good safety-type analysis, we have to embed this bookkeeping.
In order to avoid code duplication, which might be worse then premature optimization, I believe we must merge the two analyzes together. By separating the assignment of values from the bookkeeping we can visit a node, perform the bookkeeping and then perform as much analyzes on the node as we want. The only thing needed is a list of strategies that encodes a single analysis on the node.
The idea might sound a bit vague, but while I was working on the operators I already saw some duplication creeping in. Some of the strategies for both analysis only differ on the strategies to fetch or add some value, a perfect change to generalize a bit I would say.
Downs and ups
Some weeks are filled with good things, others with bad things. For me, the last week was filled with both. My parents celebrated there 30th wedding anniversary, my little brother turned 21 and my last remaining grandmother passed away. You can probably figure out yourself which ones are good and which one is bad.
So the schedule of this week was a bit out of balance because of these events. However, I still managed to get some work done. The analysis for constant-propagation and the one for the safety-levels now share the same structure. This will make it easier to generalize the analysis into a more generic framework, something which will reduce code duplication.
I have also finished my thesis proposal which means that I can now start the real graduation process. The official start date will be on March 5th, next Monday. This process is suppose to take 22 weeks, in this case until the 6th of August. Since there are some other events in between it will take some additional weeks. However, this schedule still allows me to graduate before first of September 2007, the start of the new academic year and the end of my 5th year.
Unfortunately, people keep telling me that the changes on keeping this schedule are pretty slim. Each year, only 1 or 2 students manage to graduate within 5 years, the minimal amount of time for this study. A nice challenge I would say :)
Oh, for those who are interested, my thesis proposal can be downloaded from this page. Please let me know if you have any questions/comments.
So the schedule of this week was a bit out of balance because of these events. However, I still managed to get some work done. The analysis for constant-propagation and the one for the safety-levels now share the same structure. This will make it easier to generalize the analysis into a more generic framework, something which will reduce code duplication.
I have also finished my thesis proposal which means that I can now start the real graduation process. The official start date will be on March 5th, next Monday. This process is suppose to take 22 weeks, in this case until the 6th of August. Since there are some other events in between it will take some additional weeks. However, this schedule still allows me to graduate before first of September 2007, the start of the new academic year and the end of my 5th year.
Unfortunately, people keep telling me that the changes on keeping this schedule are pretty slim. Each year, only 1 or 2 students manage to graduate within 5 years, the minimal amount of time for this study. A nice challenge I would say :)
Oh, for those who are interested, my thesis proposal can be downloaded from this page. Please let me know if you have any questions/comments.
Visiting Dublin
My girlfriend and I went to Dublin this weekend and we had a great time. We flew with Aer Lingus and stayed at the Jacobs inn. This hostel really relaxed and I can certainly recommend it to anyone who just wants to sleep low budget. We basically did some sightseeing and walked around town. On Saturday we went to Radio City Dublin to see the Heideroosjes, the coolest punk-band I know.
Radio City is a cozy basement with a bar, a stage and room for about 200 people. It looks professional, but they could improve the information flow about who is going to play when. When we asked which bands played that evening it took about 10 minutes and 4 people to tell us that they didn't have a clue. It all worked out fine though. Seeing the Heideroosjes in a place with only 20 people, half of them Dutch, was a bit weird, but they definitely rocked! We plan to see them again in the Melkweg on the 16th of March, hopefully with a bigger crowd :)
The weekend in Dublin has given me some time to think about the things I want to do this year. I have made up a little list of the most important things that I want to pursuit this year, a kind of (very late) New Year's Resolutions:
These goals are not very surprising, but they require some shift in my priorities. Let's see if I can be part of the 46% that keeps such resolutions after 6 month. I personally think that the last one will be the hardest one to keep :)
Radio City is a cozy basement with a bar, a stage and room for about 200 people. It looks professional, but they could improve the information flow about who is going to play when. When we asked which bands played that evening it took about 10 minutes and 4 people to tell us that they didn't have a clue. It all worked out fine though. Seeing the Heideroosjes in a place with only 20 people, half of them Dutch, was a bit weird, but they definitely rocked! We plan to see them again in the Melkweg on the 16th of March, hopefully with a bigger crowd :)
The weekend in Dublin has given me some time to think about the things I want to do this year. I have made up a little list of the most important things that I want to pursuit this year, a kind of (very late) New Year's Resolutions:
- Finishing my Master Thesis
- Getting a fun job
- Improving/promoting PHP-Sat
- Having an awesome World Jamboree
- Climbing a grade 6a-route
These goals are not very surprising, but they require some shift in my priorities. Let's see if I can be part of the 46% that keeps such resolutions after 6 month. I personally think that the last one will be the hardest one to keep :)
Pimping my environment(s)
You probably already noticed that the blog has been pimped. I have adopted the quote that was mentioned at the SUD, updated the links, added the logo and an overview of all the labels. The blog now represents more of what it already was, a place to write about the projects I am involved in. And yes, me is also a project I am involved in :)
Apart from the blog I also updated the PHP-Sat website. There is now some documentation for PHP-Sat and the bug-patterns. The documentation of PHP-Front will also be updated soon. The last thing I have to do is writing the friendly and catchy welcome page, always a difficult task.
We are traveling further away from the project when I tell you that I also updated my computer configuration. You might recall that I used to work on a virtual machine, which tend to be a bit slow. So my current configuration is a dual-boot system with Windows2000 and Fedora Core 6 (default).
The documentation for setting up the working environment was more or less a guide for myself to get everything working again. It was definitely worth the work of backing-up all my configurations. A complete compilation of PHP-Front and PHP-Sat now takes 10m47s instead of the old 23m37s.
The last environment that I have pimped has nothing to do with any of the projects, except the me-project. I have cleaned my room and moved some stuff around. It is surprising to see how many useless things I had and how much space you gain when you throw them out. Although I am one of those people that believes in: 'everything you throw away will be useful the next day, my trust in this claim is fading away. It has been two days now and I still do not need the four, 10 centimeters long, lightsabers collected from cereal-breakfast-boxes.
Apart from the blog I also updated the PHP-Sat website. There is now some documentation for PHP-Sat and the bug-patterns. The documentation of PHP-Front will also be updated soon. The last thing I have to do is writing the friendly and catchy welcome page, always a difficult task.
We are traveling further away from the project when I tell you that I also updated my computer configuration. You might recall that I used to work on a virtual machine, which tend to be a bit slow. So my current configuration is a dual-boot system with Windows2000 and Fedora Core 6 (default).
The documentation for setting up the working environment was more or less a guide for myself to get everything working again. It was definitely worth the work of backing-up all my configurations. A complete compilation of PHP-Front and PHP-Sat now takes 10m47s instead of the old 23m37s.
The last environment that I have pimped has nothing to do with any of the projects, except the me-project. I have cleaned my room and moved some stuff around. It is surprising to see how many useless things I had and how much space you gain when you throw them out. Although I am one of those people that believes in: 'everything you throw away will be useful the next day, my trust in this claim is fading away. It has been two days now and I still do not need the four, 10 centimeters long, lightsabers collected from cereal-breakfast-boxes.
Operator precedence
So what was the curious remark in the last blog? What is the interesting functionality that I have made? The title gives the area of the functionality away, 'Operator precedence'.
The problem with PHP, and most grammars in general, is that the operator precedence is usually ill-documented. There is some documentation in a table, but the real reference is the implementation itself. Martin has a really nice idea about how you can check two grammars on having the same operator precedence, simple yet elegant.
If you take two definitions of a grammar, for example one defined in YACC and one defined in SDF, you can extract what is allowed and what not. The process of extracting the precedence rules that encode the behavior from these formalisms is written down in the paper that is produced, but I am not sure whether or not this is put on the web before we know if it is accepted to LDTA 2007. I do not even know if I can explain this very clearly in one post. So I can not provide a link to the paper, but this might be an interesting subject to blog about for Martin. (Yes, this is a hint!)
After extracting the precedence-rules you have to rename constructs and filter extensions from the rules. Finding the exact rewrites that are necessary is easy if you first extract the production-rules that are possible. This reduces the set that you are looking at from 3000-5000 to 30-50 rules, which is much easier to examine. After the rewriting you can compare the two sets of precedence-rules by a simple diff, a built-in strategy.
So what did I do exactly? Well, I worked on the actual tools in order to get some result, and we definitely did! We found several (precedence) problems in C-Transformers and the SDF-library, which both target C. This demonstrates the great power of the tools, because I am not that familiar with C myself!
We also found some precedence problems in the PHC, which were fixed very shortly after the report was send in. I was aware of the fact that there are some problems in PHP-front regarding operator precedence. In fact, it was one of the reasons for making these tools. The number of about 400 precedence problems was a still bit overwhelming at first. But most of these problems are due to the same operators and just produce about 49 warnings because all of the other operators report an error on it. We still have a lot of work to do, but we now have tool-support for checking the precedence rules!
The problem with PHP, and most grammars in general, is that the operator precedence is usually ill-documented. There is some documentation in a table, but the real reference is the implementation itself. Martin has a really nice idea about how you can check two grammars on having the same operator precedence, simple yet elegant.
If you take two definitions of a grammar, for example one defined in YACC and one defined in SDF, you can extract what is allowed and what not. The process of extracting the precedence rules that encode the behavior from these formalisms is written down in the paper that is produced, but I am not sure whether or not this is put on the web before we know if it is accepted to LDTA 2007. I do not even know if I can explain this very clearly in one post. So I can not provide a link to the paper, but this might be an interesting subject to blog about for Martin. (Yes, this is a hint!)
After extracting the precedence-rules you have to rename constructs and filter extensions from the rules. Finding the exact rewrites that are necessary is easy if you first extract the production-rules that are possible. This reduces the set that you are looking at from 3000-5000 to 30-50 rules, which is much easier to examine. After the rewriting you can compare the two sets of precedence-rules by a simple diff, a built-in strategy.
So what did I do exactly? Well, I worked on the actual tools in order to get some result, and we definitely did! We found several (precedence) problems in C-Transformers and the SDF-library, which both target C. This demonstrates the great power of the tools, because I am not that familiar with C myself!
We also found some precedence problems in the PHC, which were fixed very shortly after the report was send in. I was aware of the fact that there are some problems in PHP-front regarding operator precedence. In fact, it was one of the reasons for making these tools. The number of about 400 precedence problems was a still bit overwhelming at first. But most of these problems are due to the same operators and just produce about 49 warnings because all of the other operators report an error on it. We still have a lot of work to do, but we now have tool-support for checking the precedence rules!
Back from Dublin
The trip to Dublin can only be subscribed as really great. My dad and I had a great time and I can really recommend it to everyone to visit this divers city.
We took an Aer Lingus flight from Amsterdam to Dublin and where only 30 minutes late, but this is something you get used to when you use the public transportation in Holland. The cab that we took drove straight through Dublin, the city is really huge! Traffic all over the place (on the wrong side of the road), almost no bikers and crowded streets. After we checked in we spend the afternoon walking around the main streets of Dublin and I went to Trinity to meet Edsko.
There seemed to be some confusion about the time of the meeting, but eventually Edsko and John showed up so we could get something to eat at the Mona Lisa. The food and the conversation was really nice. We talked about parsing PHP, the differences between the internal representations and living in Dublin. We concluded that the projects are not really compatible because the internal representations are really different. These internal representations of the PHP-sources can be made compatible from PHP-Sat to PHC, but not the other way around. The goals of the projects are also quit different, but we could probably learn something from each other. Although this conclusion is a bit of a disappointment I had a really nice time. Edsko also showed me some of the inside of Trinity College, which is definitely worth a visit. Thank you Edsko and John for a fun evening, I hope we meet again sometime.
The visit to Google was on Tuesday at 12 o'clock, so we still had to fill the morning with something useful. We visited to the national gallery which had an interesting exposition about the Irish culture in the last 200 years. They also have a (very large) collection of other paintings which were less interesting to me, but my dad seemed to like them.
And then it was finally time to go to the Google Office. Leslie could not make it because she was sick, but Rob Holland was kind enough to take over the coordination. We started the visit in the game-room which is filled with video-games, a snooker-table and a massage chair. We left our bags there and Rob showed us around the floor and the different teams. Everybody seemed to be busy, but they also took the time to say 'hi'.
After the tour we went downstairs to the restaurant. There was plenty of food (all free), drinks (all free) and ice-cream (again all free). The conversation with the engineers during lunch was very interesting. They have done some fun (and dangerous) experiments with various (expensive) toys, but they also work very hard.
We finished the visit with the lightning presentations of our projects. The topics of the projects were pretty far apart, but it is good to broaden your horizon.
The visit confirmed my expectations that working at Google is pretty cool, but you will still have to work hard. This is not so bad because the people seem to be very nice and intelligent and the atmosphere is great. Thank you Google for making this visit possible!
We flew back on Wednesday after visiting the Guinness-brewery, you just have to visit this brewery when you are in Dublin.
The overall conclusion is that the trip was fun, exciting and really interesting. It is hard to describe everything in words, but it was definitely cool!
But onto the next challenge. After spending about one hour figuring out all the dependencies for some yacc-converting tools I am going to hack some interesting functionality together. Stay tuned for more information about this incomprehensible remark.
We took an Aer Lingus flight from Amsterdam to Dublin and where only 30 minutes late, but this is something you get used to when you use the public transportation in Holland. The cab that we took drove straight through Dublin, the city is really huge! Traffic all over the place (on the wrong side of the road), almost no bikers and crowded streets. After we checked in we spend the afternoon walking around the main streets of Dublin and I went to Trinity to meet Edsko.
There seemed to be some confusion about the time of the meeting, but eventually Edsko and John showed up so we could get something to eat at the Mona Lisa. The food and the conversation was really nice. We talked about parsing PHP, the differences between the internal representations and living in Dublin. We concluded that the projects are not really compatible because the internal representations are really different. These internal representations of the PHP-sources can be made compatible from PHP-Sat to PHC, but not the other way around. The goals of the projects are also quit different, but we could probably learn something from each other. Although this conclusion is a bit of a disappointment I had a really nice time. Edsko also showed me some of the inside of Trinity College, which is definitely worth a visit. Thank you Edsko and John for a fun evening, I hope we meet again sometime.
The visit to Google was on Tuesday at 12 o'clock, so we still had to fill the morning with something useful. We visited to the national gallery which had an interesting exposition about the Irish culture in the last 200 years. They also have a (very large) collection of other paintings which were less interesting to me, but my dad seemed to like them.
And then it was finally time to go to the Google Office. Leslie could not make it because she was sick, but Rob Holland was kind enough to take over the coordination. We started the visit in the game-room which is filled with video-games, a snooker-table and a massage chair. We left our bags there and Rob showed us around the floor and the different teams. Everybody seemed to be busy, but they also took the time to say 'hi'.
After the tour we went downstairs to the restaurant. There was plenty of food (all free), drinks (all free) and ice-cream (again all free). The conversation with the engineers during lunch was very interesting. They have done some fun (and dangerous) experiments with various (expensive) toys, but they also work very hard.
We finished the visit with the lightning presentations of our projects. The topics of the projects were pretty far apart, but it is good to broaden your horizon.
The visit confirmed my expectations that working at Google is pretty cool, but you will still have to work hard. This is not so bad because the people seem to be very nice and intelligent and the atmosphere is great. Thank you Google for making this visit possible!
We flew back on Wednesday after visiting the Guinness-brewery, you just have to visit this brewery when you are in Dublin.
The overall conclusion is that the trip was fun, exciting and really interesting. It is hard to describe everything in words, but it was definitely cool!
But onto the next challenge. After spending about one hour figuring out all the dependencies for some yacc-converting tools I am going to hack some interesting functionality together. Stay tuned for more information about this incomprehensible remark.
SUD 2007 roundup
Warning: rather long story with a lot of my own opinions up ahead!
I attended my first Stratego User Days this week without really knowing what to expect. I had seen the titles of the talks, but some of them still made me wonder about what was going to be presented. So I took the train to Delft with sleepy eyes and a blank mind.
If you think that the SUD is like a conference then you are wrong, it is more of an informal gathering of people that use Stratego. They explain to each other what they do, how they handle problems and what they would like to see in the next release of Stratego. At first this gave me the idea that the room would be filled with _all_ of the users of Stratego, which was probably true for some of the earliest SUD's, but the first presentation of the day already proved that this idea was wrong. Martin Bravenboer started the SUD with a presentation about the current status of Stratego. He did not only explain how hard they worked on the 0.17 release, but also showed a list of papers and projects, including one complete slide about PHP-SAT, that use Stratego. Some of the people on this list use Stratego without any help from 'the core people', Martin and Eelco, so this probably shows that Stratego is catching on. Martin also mentioned that they are several (Phd) positions to fill, so if anybody is interested they should contact him.
Eelco Visser gave a presentation about the new compilation scheme of Stratego.The presentation was a bit too technical for me, but it showed some nice goals and resulted in a (short) discussion. The discussion ended at the moment that Eelco gave the right example by getting himself some coffee.
Martin continued after the break with a presentation about the new library structure of Stratego. He explained why almost all of the functionality is moved to the library in order to target the portability problem. The funny thing is that some of the presentations that where about to come would complain about this problem, which shows that the needs from the community are actually being fulfilled. I liked the fact that Martin gave lot's of examples that used php-front to illustrate the new features, always nice to see your own stuff used.
We had lunch a little late because we already hopelessly behind schedule, but it was still very nice. I have to say that I like the cafeteria in Delft, the money/food ratio is pretty good. The presentation of PHP-SAT started after the lunch and went very well. The people looked interested even after the moment that the laptop shut himself down because the battery was empty. Karl Trygve Kalleberg mentioned that IBM also had a project about static analysis of source code called Wala, but he did not remember whether it supported PHP. So I tried to find the PHP-part, but I could not find it so it is probably not supported.
Benoit Sigoure talked about his project in which he extended PRISM to deal with real life problems. I always enjoy it when somebody talks about projects that are really useful to them. He also mentioned some problems that he encountered and gave a 'wish list' of items he wanted to see in Stratego. I have experienced most of the problems he has and I totally agree with the fact that he wants some more static checking. One of the other wishes was a debugger and I would like to put this on top of the list. Being able to step through my Stratego program is something that would help me a lot, and others as well.
During the coffee break that followed the presentation of Benoit one of the girls in the room next-door asked me what kind of meeting we had. I explained the concepts of the SUD to here and she replayed with the phrase: ..I already thought that it was something with programming, you are all wearing those nerdy-code-t-shirts.., thank you very much indeed.
After I had probably been insulted by the girl, Mikal Ziane and Nicolas Pierron talked about Lutin. They use java-front and dryad to do some kind of code refactoring, but it wasn't completely clear to me. I think I might have understand things better if we weren't interrupted by the fire-alarm. It gave us a change to see some of the campus and the other people in the building, but it didn't help us to keep up with the schedule.
The presentation of Wouter Caarls about embedding Stratego in C showed another thing that can be done with Stratego. The techniques he used where not very complicated, most of them where also covered in program transformation course in Utrecht, but the combination was interesting.
Valentin David his presentation ended the day by giving an overview of the current C++-front-ends. This presentation was not very interesting to me because I (currently) do not use C++, but I can at least find it again when I need to. But during the talk he mentioned semantic designs, which offers support for analysis. They also have a front-end for PHP, so I probably should take the time to take a look at this.
The second day of the SUD started with a presentation about a system that comparable with Stratego, but written in Java. The system is called TOM and it has some very nice properties. They borrowed some features of Stratego and I hope we also will borrow some of their features. The small features, like matching on a sort without specifying the number of children or the not-match, are most likely not difficult to implement but useful additions to Stratego. They also showed an eclipse-plugin for their project and a graphical debugger, great things to have and very useful. Another project that is added to the list of things to checkout.
Another connection between Stratego and Java was presented by Karl Trygve Kalleberg. He showed the Spoofax project, which also holds a plugin for Eclipse. I haven't really thought about looking at this for the syntax highlighter for Context, but it might be a good idea to check how he did this.
Bernd Fischer gave a presentation about what he wanted to get from the Stratego community. Some of the ideas could also be useful for other Stratego developers, but most of his wishes could probably be solved by implementing a separate library for ACI1-terms. Some of the problems that he mentioned are actually handled by MathPert, so he might want to take a look at it.
The talk of Alexandre Borghi about vectorization was a bit to technical for me. I think I understand why you want it, but could not figure out completely how everything worked. I do not have a problem with this, I do not intend to use it in the near future, but other people will certainly find it interesting.
A presentation that was really interesting for myself was the presentation of Bogdan Dumitriu. He did his master thesis on improving support for data-flow transformations for Object-Oriented programs. Many ideas from his thesis and his talk are very useful for me and the PHP-Sat project, so I am definitely going to read the complete thesis. His support for break- and continue-constructs can easily be added to PHP-Sat and his ideas about customized transformations are definitely cool. As soon as a get a copy of the thesis, and some spare time, I will write a blog about these cool subjects.
My own version of the SUD ended with the presentation of Karl Trygve Kalleberg and Valentin David in which they present some ideas for extending Stratego. Some of the extensions, like an attribute grammar system, are already implemented in Transformers and look interesting. Other proposal are still in the 'this-would-be-a-nice-idea'-stage, so we will have to wait and see what the future brings us.
To conclude this roundup I wanted to say that the whole experience was very cool. It was nice to see what other people are doing with Stratego and was a good opportunity to do some feature-requests. I am already looking forward to the SUD of next year.
The SUD also gave raise to a great quote coming from Pierre-Ettienne Moreau which I probably will going to use more often. The quote displays a great sense of a pragmatic attitude which really appeals to me. During the presentation about TOM Pierre-Ettienne explained some side-effect that could occur during the application of a strategy. After someone asked him whether it was pure he replied:
..it is not pure, but it is practical.
I attended my first Stratego User Days this week without really knowing what to expect. I had seen the titles of the talks, but some of them still made me wonder about what was going to be presented. So I took the train to Delft with sleepy eyes and a blank mind.
If you think that the SUD is like a conference then you are wrong, it is more of an informal gathering of people that use Stratego. They explain to each other what they do, how they handle problems and what they would like to see in the next release of Stratego. At first this gave me the idea that the room would be filled with _all_ of the users of Stratego, which was probably true for some of the earliest SUD's, but the first presentation of the day already proved that this idea was wrong. Martin Bravenboer started the SUD with a presentation about the current status of Stratego. He did not only explain how hard they worked on the 0.17 release, but also showed a list of papers and projects, including one complete slide about PHP-SAT, that use Stratego. Some of the people on this list use Stratego without any help from 'the core people', Martin and Eelco, so this probably shows that Stratego is catching on. Martin also mentioned that they are several (Phd) positions to fill, so if anybody is interested they should contact him.
Eelco Visser gave a presentation about the new compilation scheme of Stratego.The presentation was a bit too technical for me, but it showed some nice goals and resulted in a (short) discussion. The discussion ended at the moment that Eelco gave the right example by getting himself some coffee.
Martin continued after the break with a presentation about the new library structure of Stratego. He explained why almost all of the functionality is moved to the library in order to target the portability problem. The funny thing is that some of the presentations that where about to come would complain about this problem, which shows that the needs from the community are actually being fulfilled. I liked the fact that Martin gave lot's of examples that used php-front to illustrate the new features, always nice to see your own stuff used.
We had lunch a little late because we already hopelessly behind schedule, but it was still very nice. I have to say that I like the cafeteria in Delft, the money/food ratio is pretty good. The presentation of PHP-SAT started after the lunch and went very well. The people looked interested even after the moment that the laptop shut himself down because the battery was empty. Karl Trygve Kalleberg mentioned that IBM also had a project about static analysis of source code called Wala, but he did not remember whether it supported PHP. So I tried to find the PHP-part, but I could not find it so it is probably not supported.
Benoit Sigoure talked about his project in which he extended PRISM to deal with real life problems. I always enjoy it when somebody talks about projects that are really useful to them. He also mentioned some problems that he encountered and gave a 'wish list' of items he wanted to see in Stratego. I have experienced most of the problems he has and I totally agree with the fact that he wants some more static checking. One of the other wishes was a debugger and I would like to put this on top of the list. Being able to step through my Stratego program is something that would help me a lot, and others as well.
During the coffee break that followed the presentation of Benoit one of the girls in the room next-door asked me what kind of meeting we had. I explained the concepts of the SUD to here and she replayed with the phrase: ..I already thought that it was something with programming, you are all wearing those nerdy-code-t-shirts.., thank you very much indeed.
After I had probably been insulted by the girl, Mikal Ziane and Nicolas Pierron talked about Lutin. They use java-front and dryad to do some kind of code refactoring, but it wasn't completely clear to me. I think I might have understand things better if we weren't interrupted by the fire-alarm. It gave us a change to see some of the campus and the other people in the building, but it didn't help us to keep up with the schedule.
The presentation of Wouter Caarls about embedding Stratego in C showed another thing that can be done with Stratego. The techniques he used where not very complicated, most of them where also covered in program transformation course in Utrecht, but the combination was interesting.
Valentin David his presentation ended the day by giving an overview of the current C++-front-ends. This presentation was not very interesting to me because I (currently) do not use C++, but I can at least find it again when I need to. But during the talk he mentioned semantic designs, which offers support for analysis. They also have a front-end for PHP, so I probably should take the time to take a look at this.
The second day of the SUD started with a presentation about a system that comparable with Stratego, but written in Java. The system is called TOM and it has some very nice properties. They borrowed some features of Stratego and I hope we also will borrow some of their features. The small features, like matching on a sort without specifying the number of children or the not-match, are most likely not difficult to implement but useful additions to Stratego. They also showed an eclipse-plugin for their project and a graphical debugger, great things to have and very useful. Another project that is added to the list of things to checkout.
Another connection between Stratego and Java was presented by Karl Trygve Kalleberg. He showed the Spoofax project, which also holds a plugin for Eclipse. I haven't really thought about looking at this for the syntax highlighter for Context, but it might be a good idea to check how he did this.
Bernd Fischer gave a presentation about what he wanted to get from the Stratego community. Some of the ideas could also be useful for other Stratego developers, but most of his wishes could probably be solved by implementing a separate library for ACI1-terms. Some of the problems that he mentioned are actually handled by MathPert, so he might want to take a look at it.
The talk of Alexandre Borghi about vectorization was a bit to technical for me. I think I understand why you want it, but could not figure out completely how everything worked. I do not have a problem with this, I do not intend to use it in the near future, but other people will certainly find it interesting.
A presentation that was really interesting for myself was the presentation of Bogdan Dumitriu. He did his master thesis on improving support for data-flow transformations for Object-Oriented programs. Many ideas from his thesis and his talk are very useful for me and the PHP-Sat project, so I am definitely going to read the complete thesis. His support for break- and continue-constructs can easily be added to PHP-Sat and his ideas about customized transformations are definitely cool. As soon as a get a copy of the thesis, and some spare time, I will write a blog about these cool subjects.
My own version of the SUD ended with the presentation of Karl Trygve Kalleberg and Valentin David in which they present some ideas for extending Stratego. Some of the extensions, like an attribute grammar system, are already implemented in Transformers and look interesting. Other proposal are still in the 'this-would-be-a-nice-idea'-stage, so we will have to wait and see what the future brings us.
To conclude this roundup I wanted to say that the whole experience was very cool. It was nice to see what other people are doing with Stratego and was a good opportunity to do some feature-requests. I am already looking forward to the SUD of next year.
The SUD also gave raise to a great quote coming from Pierre-Ettienne Moreau which I probably will going to use more often. The quote displays a great sense of a pragmatic attitude which really appeals to me. During the presentation about TOM Pierre-Ettienne explained some side-effect that could occur during the application of a strategy. After someone asked him whether it was pure he replied:
..it is not pure, but it is practical.
Interesting things
I noticed that it was already a week ago since I wrote my last blog, time flies when one is having fun. So this week should go really fast because all sorts of interesting things are going to happen!
The first interesting event is going to be the Stratego User Days where I will be presenting PHP-Sat. This presentation will be a bit more technical then my STC-presentation, but it will also contain the more theoretical stuff (I think).
The other even that is interesting, certainly for me, is that I am going to Dublin next Monday. I will be staying there for three days and I am going to do at least two interesting things there. I am part of the GSoc-group that is going to visit the Google Office. Someone else who was going to come was Paul Biggar, one of the people behind the Phc. It is to bad that I cannot meet him to talk about some of the problems/choices/gizmos involved in parsing and transforming PHP-code. But I will be meeting the other two authors of Phc. I am really looking forward to this meeting, it's going to be very interesting.
I promise that I will write about all of these events, so don't worry about missing all this interesting stuff. I am even considering to subscribe to something like Flickr so that I can share some pictures with you, although I think that the SUD will be covered by Eelco Visser.
For those people that want to read about something that actually happened already I have a little Doh-anecdote. I spend a day working on PHP-Sat together with Martin to fix the last DoubleQuoted string-ambiguities. The problem was that there where some literals that kept breaking apart within strings that where used for regular expressions. The reason for this was a missing follow restriction, so we fixed it and where very happy with ourselves. So I took another look at the problem yesterday and noticed that there where still more situations that showed this behavior. After about an hour I realized that we already fixed this problem for HereDoc by writing out the allowed order of literals and escapes. But I can not remember why we didn't do this for DoubleQuoted strings, isn't that interesting?
The first interesting event is going to be the Stratego User Days where I will be presenting PHP-Sat. This presentation will be a bit more technical then my STC-presentation, but it will also contain the more theoretical stuff (I think).
The other even that is interesting, certainly for me, is that I am going to Dublin next Monday. I will be staying there for three days and I am going to do at least two interesting things there. I am part of the GSoc-group that is going to visit the Google Office. Someone else who was going to come was Paul Biggar, one of the people behind the Phc. It is to bad that I cannot meet him to talk about some of the problems/choices/gizmos involved in parsing and transforming PHP-code. But I will be meeting the other two authors of Phc. I am really looking forward to this meeting, it's going to be very interesting.
I promise that I will write about all of these events, so don't worry about missing all this interesting stuff. I am even considering to subscribe to something like Flickr so that I can share some pictures with you, although I think that the SUD will be covered by Eelco Visser.
For those people that want to read about something that actually happened already I have a little Doh-anecdote. I spend a day working on PHP-Sat together with Martin to fix the last DoubleQuoted string-ambiguities. The problem was that there where some literals that kept breaking apart within strings that where used for regular expressions. The reason for this was a missing follow restriction, so we fixed it and where very happy with ourselves. So I took another look at the problem yesterday and noticed that there where still more situations that showed this behavior. After about an hour I realized that we already fixed this problem for HereDoc by writing out the allowed order of literals and escapes. But I can not remember why we didn't do this for DoubleQuoted strings, isn't that interesting?
Who's idea is it anyway?
I started with the research for my thesis proposal this week. For those who
wonder about the subject: please read on. For everybody else: skip to the next paragraph. My master thesis will explore an idea of Johan Jeuring
and Harrie Passier. The eventual goal is to provide feedback in educational tools (well actually educational tools that allow you to rewrite a certain input step by step to an answer), as if the feedback comes from a teacher. One of the hurdles that has to be taken is the guessing of which step the student wanted to take when a faulty answer is inserted in the program.
The idea for guessing this step is that you take the last correct tree and then generates all the trees that can be obtained by rewrite-rules that are allowed. You then calculate the difference between these trees and the faulty answer to find out which tree is nearest to the faulty answer. The rewrite-rule used to get this nearest tree is probably the rule that the student wanted to apply.
This simple and short explanation does not expose all the problems very well, but I will probably come back to that in a later blog. For more information about the idea you can take a look at this paper.
Last Monday I was in Leusden to meet the people from 'TeamInternet' again. Apart from going through some new code of the scoutshop, I also showed PHP-Sat to the people there. Bjarni van Berkum came up with a new idea for a bugpattern and this resulted in another idea. He told me that he was interested in the results of PHP-Sat on the code base because it would probably find the first pattern a few times. I told him that it shouldn't be hard to implement, but it turns out that this is not completely true.
I was right about the fact that it is easy to implement, for normal and static function calls that is. The retrieving of these functions are pretty straightforward because they are directly available in the environment. The problems lays in the fact that most of the codebase of TI is ObjectOriented, which means that there are lots of objects passed to lots of functions. But we currently do not descent into functions, nor do we know about objects. This poses somewhat of a problem if you want to find out which objects are used within functions. So unfortunately, there is a lot of work to be done in order to support this.
But there where more ideas that came from people at TI. Frits Zwegers talked about an idea for a tool that can give an overview of which files are needed for a given file. This can be done by collecting all directly included files and all the files that declare a class or a function that is used within the file. The implementation of this tool is also delayed because of the problem mentioned above, but I am pretty sure that it will be available some day :)
The people mentioned above already came up with great ideas, so if you also have a great idea: share it!
wonder about the subject: please read on. For everybody else: skip to the next paragraph. My master thesis will explore an idea of Johan Jeuring
and Harrie Passier. The eventual goal is to provide feedback in educational tools (well actually educational tools that allow you to rewrite a certain input step by step to an answer), as if the feedback comes from a teacher. One of the hurdles that has to be taken is the guessing of which step the student wanted to take when a faulty answer is inserted in the program.
The idea for guessing this step is that you take the last correct tree and then generates all the trees that can be obtained by rewrite-rules that are allowed. You then calculate the difference between these trees and the faulty answer to find out which tree is nearest to the faulty answer. The rewrite-rule used to get this nearest tree is probably the rule that the student wanted to apply.
This simple and short explanation does not expose all the problems very well, but I will probably come back to that in a later blog. For more information about the idea you can take a look at this paper.
Last Monday I was in Leusden to meet the people from 'TeamInternet' again. Apart from going through some new code of the scoutshop, I also showed PHP-Sat to the people there. Bjarni van Berkum came up with a new idea for a bugpattern and this resulted in another idea. He told me that he was interested in the results of PHP-Sat on the code base because it would probably find the first pattern a few times. I told him that it shouldn't be hard to implement, but it turns out that this is not completely true.
I was right about the fact that it is easy to implement, for normal and static function calls that is. The retrieving of these functions are pretty straightforward because they are directly available in the environment. The problems lays in the fact that most of the codebase of TI is ObjectOriented, which means that there are lots of objects passed to lots of functions. But we currently do not descent into functions, nor do we know about objects. This poses somewhat of a problem if you want to find out which objects are used within functions. So unfortunately, there is a lot of work to be done in order to support this.
But there where more ideas that came from people at TI. Frits Zwegers talked about an idea for a tool that can give an overview of which files are needed for a given file. This can be done by collecting all directly included files and all the files that declare a class or a function that is used within the file. The implementation of this tool is also delayed because of the problem mentioned above, but I am pretty sure that it will be available some day :)
The people mentioned above already came up with great ideas, so if you also have a great idea: share it!