Sunday 28 September 2014

Notable Toulousains

There are several renowned people associated with Toulouse. If you live here for some time, chances are that you'll find out on your own about 2 of them: Paul Sabatier and Pierre de Fermat, as 1 of the main faculties of the city and one of the most important Lycees (High Schools) are named after them. Another one, Jean Jaures, was also an affiliate of the city, but his presence extends over the whole country (and the Sud in particular): streets, sculptures and all sort of references. I'd never heard of him before coming here, but he seems like a really interesting man, a social-democrat (way before Social Democracy had turned into the bad joke it's now) with profound anti-militarist feelings that caused him his death in the aftermath of the WWI that so much he tried to avoid (by the way, the story of how his assassin found death in hands of Spanish Republicans is really interesting, sometimes Justice just happens).

If you ever pay a visit to the interior of Le Capitole or to the Musee des Augustins, and I would urge to do so, as both are very pleasant visits (and free each Sunday for the former and each first Sunday of the month for the latter), 2 painters will become quite well known to you: Henri Martin, and Paul Gervais. Bearing in mind that Gervais lacks of an English entry in Wikipedia, and that the one for Henri Martin is very basic (the French one is much more complete), it seems like they didn't gain much international recognition, but I find them both pretty interesting.

As for Henri Martin and his neo-impressionism, while I really like the room bearing his name in le Capitole, with different images of the Garonne (with Jean Jaures in one of them) and the year seasons (I particularly like the Autumn and Winter ones), the work that really caught my attention since the first moment is Beauté, displayed in Musee des Augustins, a really outstanding representation of female beauty.

For Paul Gervais, I mainly know his works in Le Capitole, both in his eponymous room an in La Salle des Ilustres. I've also admired his work in the Palais Consulaire (last week, during the "Journees du Patrimoine" there was free access to many buildings usually closed to the public), and I know he has some paintings in "les Augustines", but I've overlooked them in previous visits, so I have some homework for the next one. All his works known to me revolve around the same noble goal, the careful and delicate portrait of female nudity.

This is done in a very interesting way, a nude beauty that aims to be enjoyed and admired, and it achieves this by doing such contemplation a part of the scene. In all these works, these nude women are not alone, but accompanied by dressed men turned into permanent worshipers of these goddesses. In this sense, "la bain de la Padilla" is probably his most shocking work:

If this man had lived in our times, he well could have become a painter of strippers :-D

Saturday 27 September 2014

Putting Science back into Fiction

Years ago I used to be pretty much into both General Science and Science Fiction, but over the years I've been going away from it, moving towards history/geography/social issues for the former, and towards drama kind of films for the latter. For the first switch I think it's mainly due to having had the chance to do some travelling, which has awaken my early interests (when I was a kid I was crazy about geography), for the second, I just would say that in the last years I haven't come across too many good SciFic films.

With such set up, Europa Report has come as a particularly beautiful surprise. No doubt that the backbone of the story is pretty exciting, the first manned trip to Europa (that Jupiter's moon that many scientists believe could be home to other life forms), but over similarly promising base ideas the ensuing development fails miserably in too many occasions. In this case a powerful and excellent story is built upon it. A bit slow paced, a bit claustrophobic, a bit emotional, with an interesting narrative formula (parts of the story are told by external sources that seems unclear how have gained that information). No unnecessary "easy horrors" or flamboyant FX, but a beautiful portrait of the human thirst for knowledge, for understanding... and the noble willingness to sacrifice it all in that search for answers.

To me, great part of the success of this film lies on how they've been able to weave a passionate work of fiction around an appealing scientific fact, that chances are that Europa hosts life. Furthermore, it seems like they've pretty much stick to current scientific knowledge when depicting the Moon.

The aspect of the moon Europa was based for accuracy on data from NASA and JPL's maps of the moon's surface

Well, I don't think there's much more that I can say other than recommending you to watch it.

Sunday 14 September 2014

Java Closures Limitations

I had read some time ago something about the limitations of Java 8 lambdas with regards to modifying state, but I hadn't had time to test it myself. Finally I've been able to give it a go and here are my findings.

This is one of the most typical examples of closures that I can think of, a function that keeps a counter of how many times it's been invoked:

	public static Supplier<String> getPrinterCounterFails(){
		int counter = 0;
		Supplier<String> f1 = () -> {
			System.out.println("function invokation: " + Integer.toString(counter));
			counter++;
			return "a";
		};
		return f1;
	}

The compiler will reject it with this message: local variables referenced from a lambda expression must be final or effectively final

So well, I felt quite puzzled by this limitation. Closures are functions with state, Java 8 does not seem to provide that, it's more like it provides functions with immutable state.

That said, it's indeed quite easy to work around this limitation. If you're trapping a primitive value, as Java 8 forces you to declare it final you can't modify it's state, but if you Wrap that value into another object, then the reference to that object will be final, but you can change the contents of that object, hence the primitive value that you've wrapped there.

	public static Supplier<String> getPrinterCounter(){
		//don't need to explicitely set it as final, as it's not being reassigned, it's effectively final
		/*final*/ int[] counterWrapper = new int[]{0};
		Supplier<String> f1 = () -> {
			System.out.println("function invokation: " + Integer.toString(counterWrapper[0]));
			counterWrapper[0]++;
			return "a";
		};
		return f1;
	}

It's been many years since the last time I wrote any Python code (I quite liked the language at first, but over time I ended up moving away from it because of the syntax, seriously, I've turned really intolerant to "non-C syntax"), but I think to remember that closures there had this same kind of limitation.

C# closures don't have this limitation, so this code will work nicely.

	public static Action GetPrinterCounter(){
		int counter = 0;
		return () => {
			Console.WriteLine("function invokation: " + counter.ToString());
			counter++;
		};
	}

It's needless to say that the almighty JavaScript also lacks this limitation.

Well, if we think in terms of how closures are implemented, and not in terms of what a closure should be, things look more clear. In JavaScript, variable resolution is based on [[scope]], ExecutionContext Objects and so on. Basically, a function points to an object where all the arguments and local variables are stored, and that in turn points to the same kind of object in the "parent function". These objects form a chain (similar to the prototype chain) and variables are looked up in this chain of objects. With such implementation, it's clear that this limitation can not exist in JavaScript.

C# and Java have nothing to do with the above. While .Net languages and now Java support functions as first class objects, their underlying platforms, the CLR and the JVM do not. I mean, neither of them has the notion of an object being a function. In both cases lambdas (and anonymous methods) will be desugared into normal (oddly named) methods. In C#, if the function needs state (i.e. it's a closure) this method will be created in a separate class containing fields for the state trapped by the closure. I think it's the same that Scala does. Java follows a more complex approach, the method is created inside the current class, and it's not until runtime (through invokeDynamic and Lambda MetaFactory magic) that a new class (implementing the required functional interface) is created. Then, in .Net a delegate object will be used to invoke this method, in Java we'll use directly the functional interface. Please, note that the above explained for java is a rough approximation based on my incomplete understanding of how lambda translation, invokedynamic and MethodHandles work in Java, I plan to write a long post about it once I've had more time to dive into it.

The problem comes for cases where the variable trapped by the closure could be trapped by another closure, or be modified by the outer function where the closure is created. In that case the compiler would need to do some black magic so that those different variables (a local variable in the outer function, a field contained in the generated class for the Closure) are kept in sync, meaning that if one is changed to point to another memory location or contain a different value (reference vs value type/primitive type), the other does so. Java compiler designers decided not to go through that trouble and just force you to declare these variables final (or be effectively final), while C# compiler designers considered it worth the effort. This means that even code like this works nicely in C#

	public static void ComplexTest(){
		int counter = 0;
		Action a1 = () => {
			Console.WriteLine("inside a1, counter: " + counter.ToString());
			counter++;
		};
		Action a2 = () => {
			Console.WriteLine("inside a2, counter: " + counter.ToString());
			counter++;
		};
		Console.WriteLine("ComplexTest, counter: " + counter.ToString());
		a1();
		a1();
		Console.WriteLine("ComplexTest, counter: " + counter.ToString());
		a2();
                a1();
		Console.WriteLine("ComplexTest, counter: " + counter.ToString());
	}

//then invoke ComplexTest
ComplexTest();
//and this is the output
ComplexTest, counter: 0
inside a1, counter: 0
inside a1, counter: 1
ComplexTest, counter: 2
inside a2, counter: 2
inside a1, counter: 3
ComplexTest, counter: 4
output:

Indeed, I had already talked about this more than 2 years ago in this post. You'll find there more information about what the C# compiler is doing and the generated bytecodes.

Sunday 7 September 2014

Albi

Before coming to Toulouse several people told me that for sure I had to pay a visit to Carcasonne, that it was such a beautiful and impressive place. Of course once I'd had a first taste of Toulouse my next steps were visiting Bordeaux (likewise some people had insisted on how nice it was, and yes, it's an incredible place) and then visiting Carcasonne. Obviously I liked the place, "la cité" (the medieval citadel) is impressive, but the rest of the city has no much to see and as my expectations were so high I didn't feel so amazed.

On the other side, when I paid my first visit to Albi, back in February, my expectations were not that high. I mainly expected a smaller version of downtown Toulouse, which of course would be nice, but nothing new to me. Wow, once there I felt fascinated by this "ville", it's much more than a "small Toulouse". Of course, you'll draw much similarities between both old towns (and with Montauban's one), as the 3 of them make up the trinity of Languedoc-style red brick architecture. I was back in Albi a few weeks ago, and the feeling of delight was the same.

My first impressions when walking from the train station to the "Centre de Ville" reinforced that perspective of being in a small Toulouse: the tree lined old boulevards, the Jeanne d'Arc statue (you'll find them in all French cities, but I think this is the only one I remember were she's standing rather than riding a horse), a nice park with astonishing gardens (since I'm here I've gone crazy about gardens, French people have such an incredible taste for gardens, and for architecture and cakes :-) a "Monument aux Morts" that is like a brick brother of the one in Toulouse...

Once in the city center, my first view was that of the Cathedral. Yeah, it's as impressive as all guide books say. The harsh and imposing walls remind me of Los Jacobinos in Toulouse, but taken to another dimension. I remember how much it captivated me many years ago when I read that the main idea of Gothic cathedrals with their large windows and towers and those high ceilings that seem to get lost in heaven... was to make men feel so small before the power of God. That vision is taken one step further here, those walls made me feel before an unconquerable military fortress, and probably that's what their constructors aimed, as it was built in the middle of a land of "heretics" after the bloody Albingensian Crusade. Once inside, things could not get any better, it's astonishing. Those painted ceilings are like a Gothic Sistine Chapel, and then the superb Rood Screen, sporting some of the most elaborate sets of gothic stone filigrees that I can think of.

The old town is much more than the cathedral: the beautiful Saint Salvi church, the red brick medieval buildings everywhere (I've ever felt a fascination for timber-frame houses, but the brick timber-frames that you find in Languedoc are a next level), the so charming Castelviel district... but the real ice of the cake will come when once in the Berbie palace you first get the astonishing views of the garden, the Tarn river with its soft waterfall, the houses leaning over the river and the imposing bridges, it's one of those images that will stay forever in your memory. In a way, this mesmerizing view reminded me of the one that you get from the castle in Cesky Krumlov, though the houses and the river are so different, something established the connection in my mind.

After enjoying the views and the garden for a long while, you should stroll to the river walking through some of the most ancient streets in the city, cross the Pont-View to the right bank, and then cross back to the main bank via the "Pont du 22 Aout 1944" (marking the liberation of Albi from the Nazi scum, just 3 days after Toulouse) that rises proudly over the Tarn for quite some meters (this elevated position could remind you of the bridges in Porto). If you continue along the Boulevard Pompidou you'll end up in another beautiful French garden and enjoy some "modern" (after so much medieval buildings) classic French architecture. Stroll back to the station and carry these memories forever with you. Then, you can even write a crappy post that in no way can express how enjoyable this little city is.

Saturday 6 September 2014

Seul Contre Tous

Seul Contre Tous (I Stand Alone) is a quite shocking film. I was not aware of it until I got it recommended by one friend. Bearing in mind that it's the first work by Gaspar Noé, the guy behind the devastating Irreversible, I should have already laid my eyes on it long ago. Indeed, I find it odd that this film is not framed in the French Extremity genre.

We're before a rather unconventional film: the story, the narrative, the aesthetic... We could consider the leading character as a sort of Antihero, but in my concept of Antihero it's necessary to be able to gain some sort of identification with him, and in this case I can't. Having been a Vegetarian on moral basis for almost 20 years, it's clear that it would be difficult that I could feel any affection for a butcher (that's our man's "profession") from the start, but as the film goes on things don't get any better, he's a piece a shit (no matter how deeply he's been a victim of society), a rather stinky one. At several points of the story it seems like there's going to be a twist and he's going to transform into a hero, but it never happens. First, when he expounds his philosophical views on loneliness, I pretty agree on start up, but then he takes it way too far. Then, when he's in a bar and the bartender rejects to serve a coffee to a well-behaved customer just cause he's an Arab (with a "you can go for a mint-tea somewhere else" and crap like that) you think our man is going to explode and blow the head of that racist scum, but nothing happens, and furthermore, later on he'll end up showing his homophobic and racist side. About his sickening approach to sexuality, well, I think that's all I can say, sickening.

The film is set in the allegedly crisis-riddend late 80's France. I say allegedly cause also at present newspapers here (I'm still living in France, though sadly I think that only for just a few more weeks) are always talking about how stagnant the economy is and how terrifying the unemployment figures are, but being an Asturian, my notion of crisis is somehow different (25% unemployment, rows of closed shops, rows of "Gold buy and sell" shops, very aged population...). There are several shots in the film that I think try to transmit a sense of political unrest: some disgusting far-right graffiti ("our land, our blood"), walls with huge slogans asking for the vote for the PCF (French Communist Party) and CGT (one trade union).

When he was he was strolling along Lille beside that nurse I had the feeling that the architecture looked quite more British than French, well, seems it's not my mind playing tricks as you can read here

.