Carlos Alberto Notes

.Net/Mono Code Camp

2009-09-30T08:22:00.003-05:00

I will be attending next october to the .Net/Mono Code Camp, where there will be conferences about the latest goodies in .Net, as well as -of course- some of the most interesting bits in the Mono land. The event is going to take place exactly on october 17th and 18th in Tarragona, Spain, and I expect to have a lot of fun there.

I will be giving a general Mono presentation with our last bits here and there, and since none of our great Moonlight hackers is coming, I will be also giving a talk about the Moonlight land. But the most interesting part is that hacker extraordinaire Lluis Sanchez is comingo talk about the awesome MonoDevelop as well as about Mono.Addins, a powerful plugin framework used in the previously mentioned project.

I think it's will also be interesting that the Codice Software crew, the guys behind Plastic SCM, will be there to give a talk also. They have been of great help for us, giving feedback, filling bugs, sending patches, etc. Their talk will be about their experience using Mono as a cross platform solution, which I'm already looking forward.

The agenda, just as Lluis mentions, include Mono, Moonlight, MonoTouch (development for the iPhone), MonoDevelop, Mono.Addins, and much more.

EDIT: Oops, I forgot to say that the registrarion is open - so, if you plan to attend, register here.

Working in an office

2008-09-11T10:07:00.003-05:00

Just like Lluis, I had been working alone from home for the last years, and after some time I began to feel a little curious about working in an office (which I had never done before), which would also mean: see real people every day, less distractions, free coffee, etc.

So I had the chance to work in the Suse Prague offices for a pair of weeks, and I have to say that even if it was only for some days, I began to feel a little more focused and less distracted (and it would be better if we had any Mono hacker around ;-) ).

Besides that, the obvious: Prague is a quite nice city, with castles, statues, and a lot of cheap and very good beer.

Hopefully I will be able to work in an office the next year - somewhere ;-)

BindingSource 2.0

2008-05-28T15:36:00.004-05:00

Following Jonathan Pobst big finale, I was immediately going to write about BindingSource (2.0 windows.forms, data binding class) and the fact that it's behaviour is not deeply explained the msdn docs (I realized this after implementing some bits based on pure sample testing and deductions, having descriptions like "returns X, Y member", which was clearly not enough in some cases).

Even if we have now tests for every 2.0 member of data binding and BindingSource, I still have the feeling that we probably are missing some bits on that class, and that's why I'm requesting everyone out there using data binding to test your app with Mono!

Observe that I have already been trying a pair of small/medium apps using it, but nothing interesting has appeared yet. That will change soon, hopefully.

Y sobre Moonlight

2007-09-08T10:39:00.000-05:00

Well, this is a basically a post in spanish, because basically I have to explain and say some things about Moonlight to some pals here around. And because I'm pretty sure some others will do the same in english (beginning with Miguel), then I proceed.

Sobre Moonlight patentes y chismes varios

Una de las cosas que más ha dado de hablar en los últimos días es precisamente la cooperación para entre Novell y Microsoft con respecto a Moonlight (nuestra versión de Silverlight). Sabíamos de antemano que por una parte, habría muchas preguntas y cuestiones importantes a aclarar, y al mismo tiempo, mucha gente diciendo cosas sin el menor sustento (como es muy común en el SL).

Ahora, primero quiero aclarar que esto no es tan fácil como decir si reprobamos o no nuestro curso, o si fuimos honestos. Las fábulas no nos sirven en muchas escenarios, como éste, precisamente.

Ahora, la cuestión en efecto es que hay una parte de la colaboración que establece que al descargar Moonlight de los sitios de Novell no hay problemas en cuanto a patentes.

Y el tema de patentes desde luego está lejos de ser un tema fácil, pero también es cierto que la gente no suele tener una *che idea de lo que realmente es. Como muchas personas lo han dicho ya, es un problema importante en la industria del software, porque por una parte se están patentando ideas que son la progresión natural de otras, y por otra parte, se patentan cosas ya hechas hace mucho tiempo. En otras palabras, el sistema de patentes apesta.

Ahora, afirmar que Moonlight no es libre porque al descargarlo bajo ciertas circunstancias es muy probable que te demanden (lo cual, no, no es chido) está lejos de ser cierto. Es decir, se pueden recibir demandas casi por cualquier cosa hecha, porque muchas técnicas de software ya están patentadas. Así que no importa si usas Python o si usas C, o si usas C# o Perl, porque puede que te caiga una demanda por patentes, y eso te puede caer -patentes- sobre cualquier aplicación de SL. Entendámonos: que puedas ser demandado por violación de patentes no hace que tu software deje de ser libre.

Ahora, en mi opinión, la cuestión tiene más que ver con una cierta desconfianza hacia Microsoft, por que se argumenta de sus prácticas nocivas y demás. Pero bueno, eso tendré que mencionarlo en otro post.

* Curiosidad: La técnica de listas ligadas que todo programador usa, y que data de hace un par de décadas, ha sido patentada recientemente. Así que como seguramente Gnome o KDE usan las listas ligadas, y por tanto, pueden ser demandadas por violar dicha patente, automágicamente dejan ambos proyectos de ser libres (según el incorrecto razonamiento previo, por supuesto).

Abortion in Mexico

2007-04-01T18:00:00.000-05:00

Abortion has always been a difficult topic, and much more in Mexico. In the latest weeks it was proposed in the Legislative Assembly of Mexico’s Federal District to legalize the partial decriminalization of abort, which caused the furious answer of the right-wing in Mexico, that in union with a group of business men and the catolic church, is trying to use again the fear campaign used the last year agains left-wing candidate to the federal government.

Human Rights Watch has an article about decriminalizing abortion. Here some interesting bits:

Safe and legal access to abortion is a human rights concern. All of our experiences have shown that women suffer terrible consequences when access to abortion is blocked and criminalized.

The deputies are also considering reforms to improve access to contraceptives and to sex education and information.

Here a related note in spanish.

Abortion and the right wing

Proceso has also an interesting article about the reaction of the right wing, which is trying to stop the decriminalization. The problem begins with the not-recognized-by-me president, Fecal.

Felipe Calderon, president of Mexico, representant of the mexican lay state, has broken the legality by declaring against the decriminalization of the abortion, using catolic terms.

As in the campaign of the 2006, the PAN people, business men, the conservative catolic church and Calderon are again using the television with his campaign against the PRD.

In 2006 the dirty campaign designed by the norteamerican Dick Morris, hired by Calderon and the PAN gave as result a confronted society. Now in 2007 the new campaign of the PAN, together with the catolic church and the business men of right wing have began not only to divide the mexican society, but to polarize it.

The health secretary, José Ángel Córdoba said the that the last year there were only 88 deaths by this cause. However, the PRD is using oficial numbers of the National Poblation Bureau (CONAPO) showing that in Mexico there are 533 thousend abortions per year in unhealthy conditions and with mortal risks.

Televisa is showing interviews and notes about women who are regretful of abortion. But there's no information about the women who have decided to abort by economical, familiar, social or even health aspects.

The article in spanish here.

The Power

2007-03-28T12:15:00.000-06:00

Today I found this really nice image:

Definitely Elba Esther Gordillo is getting payed by the help she gave to the not-recognized-by-a-lot-of-people president Calderon in his dirty campaign last year. The last proof of that is the recent change to the ISSTE.

The dirty game of the right wing in Mexico

2007-02-18T13:34:00.000-06:00

In the latest days, the historian Carlos Tello Diaz presented his book "2 de Julio", where he mentions that, based on his own sources, Andres Manuel Lopez Obrador (the federal government candidate for the left wing), accepted he lost the elections.

In an interview, he also mentioned he had the chance to talk to Perez Gay and Federico Arreola (who are close to Lopez Obrador) to corroborate it.

However, he's having a lack of credibility: Perez Gay denied he gave an interview to Tello Diaz, in an article published a day later. Also, Federico Arreola had the chance to face him in an interview with Carmen Aristegui (one of the most prominent journalist in Mexico), where Tello couldn't bear with the pressure.

As Federico Arreola mentions in his article, it's part fo the dirty game from the federal government.

Le exigí que probara que AMLO había dicho eso. No pudo hacerlo. Lo reté a que diera el nombre de su fuente, se negó varias veces. Insistí y Tello no soportó la presión. Me acusó: "Tú fuiste la fuente". Cuando le expliqué que lo iba a llevar a los tribunales por esa calumnia, reculó: "Miento en eso, efectivamente".

Weird enough, we also have in Mexico one of the worst journalist out there: Lopez Doriga, who writes a columns saying "we already knew that Lopez Obrador knew about his lost". Well, if you say to, then _prove it_.

The high prices of corn and other bits.

In the campaign for the federal government, Calderon (currently the presidente of Mexico, legal but not legitimate) said that Lopez Obrador was a "danger for Mexico". As part of those aseverations, he said "the prices will get higher". What does he have to say now, when whe have these high prices in corn?

Interesting enough, a lot of people around me that used to think about of Lopez Obrador as a "danger for Mexico" don't even say a word about it. I wonder why.

The rigth wing in Mexico

2006-12-09T15:37:00.000-06:00

Wow, it's incredibly surprising how they right wing in Mexico is trying to put and end to the public education. I just found this note in a newspaper:

La Secretaría de Educación Pública (SEP) hizo un llamado a los rectores de las universidades públicas del país a iniciar un debate “serio” para imponer cuotas a los estudiantes y crear un sistema de créditos, debido a que en este momento más de un millón de jóvenes, es decir, 40 por ciento de la matrícula nacional, recibe un subsidio que es 12 veces mayor que el de estudiantes provenientes de zonas indígenas o de escasos recursos.

It basically says that the federal government made a call to the public universities to begin a debate to impose fees. This is very interesting, because there's a very clear idea to end with the public education based on the next principles:

a) The education should be privatized, since it has large costs for the government

b) Only a few should be able to receive high-quality education: those who can pay a private school

c) The handcraft should have priority over the education. We are a handcraft country, after all.

d) It's easier to gain control over the students in the private universities; at least that's the case in Mexico (observe that I'm not against the private education. I'm saying that the private education trends to sucks IN Mexico). Some of those universities have given us the worst politicians and businessmen.

e) In some universities -such the UNAM- there's a big concentration of left-winged groups, which could be a problem for the right-winged governments. So, let's end with them too.

here

The current status of the problem in Oaxaca

2006-10-30T14:18:00.000-06:00

For the mexican audience, it's not a secret that the problems arising in Oaxaca are related to the abuses committed by the government of the state. Right now the scenario appears to be pretty complicated, and different groups in the country are showing their dislike for the use of the army by the federal government (around 7 persons have been killed in the last days).

Usually it's nice to read articles and essays by the international media, telling the truth about the circumstances in the international events. I used to read DW (Deutsche Welle), until I found this stupid paragraph:

El presidente de México, Vicente Fox, se acerca al último mes de su gobierno con un nivel de popularidad muy superior al de otros mandatarios latinoamericanos. Por ello, son muchos los mexicanos que seguramente aplaudirán el envió de tropas policíacas a Oaxaca

First of all, Fox hasn't a very good popularity here in Mexico. Even more, he is shown as a clown by the media. Second, the mexican nation isn't very happy about the army trying to take Oaxaca. The demonstration taking place along the entire country are a proof of that.

Hey, trolls

2006-07-14T17:29:00.000-05:00

Hey trolls. Yes, you trolls. Since you can't understand the things written by the media (and by media, I mean Proceso, Jornada, Mileno, and similar), I want to put these pictures. They are very easy to understand.

Since these goodies are very easy to understand, I highly recommend: http://www.monerohernandez.com/

Of course, you could also try to read good articles (forget about Cronica and such).

PD - I beg your pardon for such hard words.

Ellos no se lo merecen

2006-07-05T16:21:00.000-05:00

Elections in Mexico

2006-07-04T00:25:00.000-05:00

The mexican media says that PRD -left wing- and the PAN -right wing- have a technical draw.

BUT it's very clear that the government and the IFE president, Luis Carlos Ugalde, are trying to manipulate the elections.

BEFORE other thing, go read: Sendero del peje, and the great post of Miguel de Icaza. I love the next parafraphs:

The PAN orchestrated a fear campaign against the PRD/AMLO. The TV ads were fairly blunt "if they win, you will loose your job and your house", "Four families will be forced to live in an apartment", your standard cold-war era propaganda. I figured nobody would believe this sort of thing, but I was surprised to listen to my own friends echo these things back to me "we would have lost our houses and jobs".
Anyways, Mexicans, like the Americans two years ago, managed to vote against their own interest as the discussion shifted away from the Economic Policy to whether the man had finished his degree and whether he ate babies with his bare hands.

From La Jornada

2006-06-09T13:15:00.000-05:00

From http://www.jornada.unam.mx:

El empresario Diego Hildebrando Zavala admitió ayer que su empresa Meta Data obtuvo pingües contratos por adjudicación directa en el sector público, y particularmente en el ámbito de Pemex, en tiempos en que su cuñado, Felipe Calderón Hinojosa, era titular de la Secretaría de Energía, de la que depende la paraestatal. La confirmación es relevante en dos sentidos: porque arroja luz sobre lo que podría denominarse, parafraseando a Daniel Cosío Villegas, el estilo personal de adjudicar que ha caracterizado al foxismo, y cuya expresión más lamentable es el conjunto de turbiedades institucionales operadas para beneficiar a los hermanos Bribiesca Sahagún, y porque coloca en un callejón sin salida la candidatura presidencial del propio Calderón Hinojosa y, con ella, al conjunto del foxismo.

But Televisa and TvAzteca think different. The reason should be obvious.

Last night debate

2006-06-07T10:29:00.000-05:00

Last night it took place the last debate in the federal elections of Mexico. For me, it was very clear that the current government with the most powerful television channels (Televisa and TvAzteca) would try to show its candidate as the winner. So, it's no surprise that Calderon -right wing side of the politics in Mexico- is saying that he won the debate.

I wrote a small essay about this situation, called "Acerca del debate". Also, from an article in Proceso, I extract the next fragment -in spanish-. A reporter asks Calderon:

Un reportero le preguntó si estaba, también, preparado para la derrota, pero él dijo que sólo piensa en el triunfo, tal como lo ha venido logrando.

--Le reitero la pregunta. ¿Está preparado para una derrota?

--Le reitero la respuesta. No –dijo, y siguió sonriendo, como lo hizo hoy durante todo el día.

So, now you know what to expect.

My essay at: www.lazurda.org
The Proceso reference: http://www.proceso.com.mx/elecciones06/not_calderon.html?nid=41113

Another one bites the dust

2006-04-20T18:51:00.000-05:00

It was time for the government of the DF to show that one of the most used arguments by the right-wing of the political escenario in Mexico was a lie:

http://www.jornada.unam.mx/ultimas/index.php?id=capital1145569886.xml&partner=rss

For me, that was clear -after some reading, of course-. But a lot of people used to take this lie as a truth.

Interesing article about the PAN campaign (in spanish)

2006-04-13T15:40:00.000-05:00

Un interesante ensayo en Proceso analiza la forma en que la campaña del PAN ha ido ganando adeptos. Un parrafo interesante resulta ser éste:

Las propuestas han quedado de lado y sus embestidas en contra de Andrés Manuel López Obrador, aspirante presidencial de la coalición Por el Bien de Todos, calificándolo de un peligro para el país, parecen darle frutos.

Y todavía más interesante ver cómo muchas personas mal informadas, se dejan llevar por el miedo:

“Es un peligro para México”, “¡Imagínate si llega a la Presidencia, lo que no hará!”, “Es un populista y sólo los imbéciles pueden creer que ayudará a sacar al país de la pobreza con su programa de viejecitos”, son algunas de las expresiones que más he escuchado en los últimos días.

Y lo más interesante del artículo:

La crispación de los actores sociales llevaría a escenarios de confrontación social y eso no conviene a nadie o, mejor dicho, sólo a algunos. El miedo inhibe la participación y, de acuerdo con las cuentas que hacen los equipos de campaña de los tres principales candidatos, el PRI es el más beneficiado, pues cuenta con una reserva de voto duro mayor que la del PRD y PAN.

Lectura OBLIGADA: http://www.proceso.com.mx/anapol.html?aid=39426

The answer of the intellectuals

2006-04-12T22:58:00.000-05:00

One or two days ago, I wrote about the way the PAN -right wing of the political groups in Mexico- bases its campaign in lies, instead of proposes.

Today I found in La Jornada -one of the most important newspapers in Mexico- some great articles, containing answers to the PAN actions -specially to the declarations of Manuel Espino, the federal president of this political group-, and one of the most interesting declarations, is the one by Raquel Tibol, artist and art critic:

"Qué han respondido sobre el Fobaproa? Qué han respondido sobre los 3 millones (de pesos) que sacó (Felipe) Caldern de Banobras? Qué han respondido acerca de las agresiones sufridas por destacadas figuras de su propio partido que al clamar por un poco de democracia interna se han visto obligados a renunciar?

And this one from writer Federico Campbell:

Estén preparando a la opinin pública para hacer posible un gran fraude electoral, en esencia esa es su estrategia, y en ese proyecto están tanto Televisa, como el PRI.

(Spanish) Como ciudadanos y ciudadanas de Mxico, tenemos la responsabilidad de estar bien informados de las verdades detrs de las bambalinas, de sas que no se salen en Televisa o Tvazteca. No es incorrecto apoyar a partidos como el PRI o PAN. Lo que es incorrecto es apoyarlos sin saber lo que hay detrás.

Referencias (MUST READ!)
* Espino y PAN muestran su ignorancia al atacar a Poniatowska (http://www.jornada.unam.mx/2006/04/12/010n1pol.php)
* De Fernando del Paso a Manuel Espino (http://www.jornada.unam.mx/2006/04/12/009n2pol.php)
* Todos somos sospechosos (http://www.jornada.unam.mx/2006/04/12/009n3pol.php)

Politics, Poniatowska and more

2006-04-10T17:12:00.000-05:00

For me, the way the PAN -mexican right winged political group- has been managing its publicity is nothing new. For me, that political group -and also the PRI, I must say- has been using political strategies that makes me remember that ones of Goebbel's (Hittler's minister of propaganda).

Recently, one of the most admired writers in Mexico, Elena Poniatowska, appeared in the mexican TV supporting López Obrador -the candidate of the left side of politics-.

It's very sad -and when I say sad, I really mean it- that a so ignorant group like the PAN comes to -indirectly- attack Poniatowska.

Fernando del Paso, also writer, also comments:
"Los otros espots que he visto, como en el que comparan a López Obrador con Hugo Chávez, de Venezuela, o el de los ladrillos que se derrumban, me parecen también siniestros. Es evidente que si estos señores no tienen nada que decir, salvo injuriar e insultar, deberían callarse.

The reference: http://www.jornada.unam.mx/2006/04/10/003n1pol.php

Interesting article about political surveys in Mexico

2006-03-03T14:11:00.000-06:00

Altought the big players in the tv in Mexico use to report wrong information, it's always nice to find that it's still possible to find good articles regarding to political activities in Mexico.

A good article about the way some political groups (specially the right wing, the PAN) use this information and try to play with it here.

Linux world event

2006-02-17T20:43:00.000-06:00

Yesterday I had the oportunity to go to the Linux Expo here and Mexico, and also had the chance to meet with my boss Miguel, and also could meet some of the Novell Ximian guys there.

If you took a photo with Miguel and me, send it to calberto.cortez at gmail (I forgot to take photos by myself). I will appreciate it.

Interesting article about politics in Mexico

2005-12-28T16:51:00.000-06:00

It's sad to see that the current government is helping some of the men behind the FOBAPROA in Mexico (a large fraud that took place some years ago, where the banks lent themselves money and then declared to be in economical problems). One of those men, Jorge Lankenau, was set free some days ago.

The article here (in spanish).

Managed environments and Macs

Miguel has a pretty interesting post about .Net/Mono environments and the declarations about it made by the mac guys (saying that managed languages are 'SLOW').

The technical issues mentioned by Miguel are really interesting, but the article also shows the way in which osnews/oreilly/slashdot 'trolly' posts should be fighted. It's more interesting to see a complete point of view, instead of the classical posts, such "I agree, that thing just sucks", "And what about the patent issue?" and that kind of posts that definitely don't help the discussion.

Nice article about the latest survey in Mexico

2005-11-25T13:48:00.000-06:00

Just found a very nice article about the latest political survey in Mexico. It points out an important fact about this kind of surveys and also mentions a different one by another institute.

The link here (in spanish)

Another article about politics in Mexico

2005-08-19T15:59:00.000-05:00

Proceso is a very good reading for those who could be interested in the social an political movements happening in Mexico.

This time I found an essay about the latest appareance of Carlos Salinas de Gortari, who was president of Mexico some years ago, and who has a lot of political power. The possible reasons behind he appearing are here.

Politics and globalization

2005-08-17T02:22:00.000-05:00

I found quite interesting an article about a thing that is known for much of us, but that remain unknown for others: the latest economical and political ideas are having a very bad impact in countries like Mexico and the located in center and south America, like social segregation, a minority with much money and so on.

A great article here, at Deutsche Welle, http://www.dw-tv.com/dw/article/0,1564,1681370,00.html

The new Marcos show

2005-08-11T15:04:00.000-05:00

The latest declarations of Marcos, one of the most important men behind the EZLN -this in Mexico-, are quite interesting, since one can't tell the _true_ reasons behind them. Why to bring them right now, when the federal elections are near? Why did he break relations with the PRD?

A very good essay about this fact here

Very good article about the current political show in Mexico

2005-04-18T16:10:00.000-05:00

I just read a very good article about the political show that was begun by our not very good president and basically the two right handed political groups in Mexico, and what causes could it bring.

The article here.

International day of the elimination of the discrimination

2005-03-21T16:16:00.000-06:00

I found that today is the International Day of the elimination of the discrimination.

Probably in a lot of places there's almost nothing of it, but there still are places where there is a lot, in a way or another.

Here in Mexico, we have some kind of implicit discrimination, where the people with power, money, or thins like that feel they have more value than others.

A good article is here: http://www.dw-tv.com/dw/article/0,1564,1525039,00.html

Good article about politics in Mexico

2005-03-04T14:42:00.000-06:00

Here is a good article about politics in Mexico, and the problem of having such bad politicians and what they can do to get the power.

Reflection only now supported in Mono

2005-02-25T07:09:00.000-06:00

I've finally committed the code to support Reflection only methods in Mono to the SVN repository. Basically, the methods are designed to be useful in those cases when only metadata is needed, and no methods/fields/properties are used/invoked. This is specially good with tools that only need to load the metadata information (such method name, parameter types, field types, etc) to show app information, or have special neeeds.

A good description can be found here. This new api will be part of the next release of .Net (Whidbey), and currently no more information is avalaible.

However, here I have some additional details:

Reflection only and non reflection only assemblies are loaded separately, which means that it is possible to have loaded in both ways the same assembly.

MemberInfo and other elements will throw InvalidOperationException when calling Invoke(), which is the exception used to warn that the members are in a reflection only assembly, and thus can not be invoked/assigned.

References are not automatically loaded, which means that all of them should be manually loaded. Mscorlib is the only one that is not needed in this form, and currently we use the loaded one as if it were a reflecion only. Note that we *could* change this in the future, altought I don't think it will happen.

Custom Attributes are retrieved in the form of CustomAttributeData class, which contains the attribute information in a 'raw' way. CustomAttributeTypedArgument and CustomAttributeNamedArgument structs will contain the information about typed and named argument, respectively. (Note: We currently don't support this; however, I hope to have them in SVN as quick as I can)

Something very important to be noted, is the fact that we currently don't avoid the creation of some inneccesary data structures for ReflectionOnly assemblies. That will likely change in the next days/weeks/months, and it's a matter of performance, not of behavior (the impact is not that big).

Thanks to Zoltan and Paolo for their help.

I'm in Monologue!!!

2005-02-24T03:43:00.000-06:00

Yeah, the next post will be the first one in being included in Monologue (sindicalization around Mono project).

Monologue can be found here.

Great essay about the current the most known political problem in Mexico

2005-02-18T17:48:00.000-06:00

Found a great article about the political situation against Manuel Lopez Obrador, where together the two most important political groups, with the current federal government, try to keep him out of the electionf for president next 2006. The link, at Proceso, here.

Problems with the C Mono api

2005-02-11T03:57:00.000-06:00

I spent almost a day solving a small problem I had creating structs from the C Mono api. When I returned this instance of struct, an exception was thrown, advising that it was not having a value...

Struct types in Mono are value based types, and since that, they cannot be null. Based in this, I could not figure out the reason for the exception. Then I remembered a similar problem I had when I defined a function, returning a MonoObject * (MonoObject* is the representation of the object C# type), that did not return the correct value (I forgot to add the return statement).

To create an instance in the C api, the class must be passed (a look into mono/samples/embed is a good beginning to begin to understand the C api), which is a MonoClass*. So, with classes you do:


MonoObject *obj;
...
/* mono_object_new (MonoDomain *d, MonoClass *klass)
 * receives as first arg the current domain and a pointer to
 * a defined class */
obj = mono_object_new (mono_domain_get (), klass);

/* Constructors must be called (they are common MonoMethod*'s) after the object is
 * created; basically, with mono_object_new the object is only allocated.
 * Note: mono_runtime_invoke (MonoMethod*, MonoObject*, 
 *       void **params, MonoObject **exception)
*/
mono_runtime_invoke (ctor, obj, params, NULL);

/* Return a fresh instance, with its constructor called */
return obj;

But..., there is the trick for structs (I had to go and read the code of Reflection after a day suffering. Mental note: remember to go to check the code when having a weird error). The trick here, is to unbox the struct before calling the constructor. Structs are allocated as value types, and finishing the stack frame where they were defined (the function itself), they dissapear. Boxing refers to the process of allocating a structure (and anything value based) as a reference type. Unbox is the oposite.

So, we would have this code for structs:


/* First, create the instance, boxed */
obj = mono_object_new (mono_domain_get (), klass);

/* Unbox on a void* variable */
o = mono_object_unbox (obj);

/* Call the method/constructor on the unboxed */
mono_runtime_invoke (ctor, o, params, NULL);

/* But ... return the MonoObject* representation */
return obj;

The question here is: structs created from the C Mono api must be created using mono_object_new, which creates boxed structs? The answer is: yes. The runtime can know the times of structs, but, the hacker would not be able to know this, even at compile time.

I hope this helps anybody (in the future, mostly) to avoid this problem.

Latest news

2005-02-04T22:26:00.000-06:00

Haven't post recently, mainly because I've been doing some work that is not very fun to be shown here.

Anyway, we are releasing Mono 1.1.4, which is the development version, and we will mark it as stabler than the 1.X series, because of minor number of bugs, better performance, and more features.

Yesterday had chance to met Miguel de Icaza at a conference that took pace at the UNAM, in Mexico city, and finally received my so long-time-wished Mono t-shirt ;-)

Finally, I want to share my my very friends a very delicious and bright idea of my friend Mauricio, who, in a moment of ilumination -both alcoholic and sex ..ehr, I mean, intelectual- reached the maximum state of inteligence, and changed the way I see the world now:

We are ugly man, we are ugly

(We was explaining me the big importance of having charisma with ladies, and how, being that much awful and super mega ultra ugly, just like he himself is, can someone be a 'ladiesman', and refering to both of us when he said that of 'we are ...').

Thanks Maurimal. You have changed the world ;-)

More work on ReflectionOnly apis

2005-01-12T20:57:00.000-06:00

I've been keeping working around ReflectionOnly apis. Last week I sent a patch to the list, waiting for Paolo/Zoltan aproval. I didn't receive any answer in the next days; however, I jsut got this from Zoltan:

Most of the code looks ok to me. However, my code review skills are
not very good. Better
wait until Paolo reviews it.

Les Miserables
Today finished the book "Les Miserables", from the hand of Victor Hugo, one of the greatest writers all of times, without any doubt. I have to say that this has been the hardest book I have ever read, and also one of my favorites -with Oscar Wilde's Portrait of Dorian Gray and Alejandro Dumas' Count of Montechrist-.

It is definitely an excellent reference to understand the person as a unit of the society, and to begin to act as good person. Certainly, it is sad, but the reward is huge. A good way to find a hope -and also get a compromise- in this society, in which, at least in Mexico, the sadness and injustice are very common things. The discrimination, implicit or explicit, based on the color of your skin, your eyes, your hair, your economical status, the car you have, and even your beliefs, are examples. Fortunately, I thinkg that we have also persons who belive that the world can be changed for good, and better, they act to make it sure.

The Hobbit
Some days ago I read that David Limon ended the book "The hobbit". Since I read the three last books, I found his description very pleasant, and I want to read it.

ReflectionOnly apis

2004-12-31T20:31:00.000-06:00

Since I want to end this year with a good thing, I will talk about a new mini api contained in the 2.0 version of .Net, called ReflectionOnly. As its title says, this is a group of methods that load assemblies and retrieve the metainformation. The difference with the Load methods, is that the last retrieve information and also prepare the environment to execute code contained withint them (late binding is something that uses this feature).

Since there can be time when it is important to only load the metainformation -based on performance, for example-, ReflectionOnly methods help that.

Probably we will include this in Mono in the next weeks, as long as I finish the methods -currently I have a working Assembly.ReflectionOnlyLoadFrom method- and let them to be reviewed by the jit guys.

Below an example:




using System;

using System.Reflection;



 public class Tester {



         static void Main ()

         {

                 Assembly ass1, ass2;



                 AppDomain.CurrentDomain.AssemblyLoad += OnAssemblyLoad;



                 ass1 = Assembly.ReflectionOnlyLoadFrom ("AssemblyRefParent.dll");

                 ass2 = Assembly.ReflectionOnlyLoadFrom ("AssemblyRefChild.dll");



                 Type t = ass2.GetType ("Child");

                 if (t == null) {

                         Console.WriteLine ("Type Child could not be loaded");

                         return;

                 }



                 Console.WriteLine ("Parent of Child = {0}", t.BaseType.Name);



                 Console.WriteLine ("ReflectionOnly Assemblies:");

                 foreach (Assembly a in AppDomain.CurrentDomain.GetAssemblies ()) {

                         Console.WriteLine ("\t{0}, ReflectionOnly = {1}", a.FullName, a.ReflectionOnly);

                 }



         }



         static void OnAssemblyLoad (object o, AssemblyLoadEventArgs args)

         {

                 Assembly loaded = args.LoadedAssembly;



                 Console.WriteLine ("Assembly Loaded = {0}", loaded.FullName);

                 Console.WriteLine ("Is Reflection Only = {0}\n", loaded.ReflectionOnly);

         }



 }

Output


Assembly Loaded = AssemblyRefParent, Culture=neutral

Is Reflection Only = True



Assembly Loaded = AssemblyRefChild, Culture=neutral

Is Reflection Only = True



Parent of Child = Parent

ReflectionOnly Assemblies:

        AssemblyRefDriver, Culture=neutral, ReflectionOnly = False

        mscorlib, Version=2.0.3600.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, ReflectionOnly = False

        AssemblyRefChild, Culture=neutral, ReflectionOnly = True

        AssemblyRefParent, Culture=neutral, ReflectionOnly = True

My wishes for the next year

2004-12-30T23:52:00.000-06:00

This has been a year with good and bad things. But for the next year, I have my purposes and things to do, and also my wishes for the three wise men (as we call him in Mexico).
My wishes are:

Be hired in a *certain* company.
A laptop (today everybody has a laptop, except me).

And because I could not get my wishes done, I add them to next purposes:

Work in the new GC engine for Mono
Move to a different city (Boston or Frankfurt would be ok ;-) )
Finish a novel in which I'm working on (an be a good one, I don't want to be one of the so many geeks that _try_ to be good writers)

Great article about the Mexico gov

2004-12-18T17:33:00.000-06:00

Today I found a very interesting article (in Spanish) about the mexican governmentm, and the reasons that show that we have to improve tons of things.

Unfortunately, as I have mentioned earlier, in Mexico it is more difficult to deliver this kind of information to the people, because of the government managed news, because of the paid political magazines, and because the people here in Mexico is used to believe everything shown in TV.

Currently I just can say that I see in Manuel Lopez Obrador the best choice for president in next 2006 elections, against the bad options that the two other main political groups could offer us.

The link here.

Mono VM Docs

2004-12-13T01:12:00.000-06:00

Miguel reported that now the docs for the Mono VM (Reflection, Internal calls, JIT, GC Handles, Interpreter, IO Layout,...) are avalaible to be seen in monodoc.

Note, however, that work for documenting them is needed. Currently, however, some of them are a little documented, and other can be just be seen (which is a good things, since I won't need to look the namesof the functions).

A screenshot below:

Mono 1.1.3 released

2004-12-09T15:29:00.000-06:00

Mono 1.1.3 was released yesterday. The mos important changes are:

New build system

SSAPRE (Common subexpression elimination)

Full support for Mono.C5 (Generics library) in gmcs

Bundles (mechanism to bundle in a single binary the Mono runtime)

Support for the /doc option in mcs

C# 2.0 new features (contravariance/covariance and properties accessors modifiers)

The last features added to mcs were made by me ;-)

Education Problems

2004-12-07T15:04:00.000-06:00

Read at DW that Germany is currently having problems with its education system, because some students leave the school when the are still young (this also is a consequence of the education system). And it also points out that in Germany the success the students get is involved with their economical situation.

At least there they have good schools, and they are now trying to improve the educations system. In Mexico we have several problems, and the current government (that being said, the last government monopoly and the current one) is not improving the system, but just making it worse.

How? creating more techinical universities, technical high schools, which shows that the government is just interested in producing qualified workers for the big companies.

Second, the more money you have, the better work you get. If you go to a expensive (very expensive) private school/university, you get almost the same education you could gain in a public one, but with more expensive builds *and*, more important, you get the sympathy of the companies. If you studied in a public university, you have fewer probabilities to get a decent job than if you studied at a particular one. Worse, the education you get there is usually not as good (or not that bad) as the one you could get ina public universitie.

Third, I thinkg we have a matter of vision and the ideas we get. Students at public universities receive an excelent education, _but_ they are educated to serve and not to manage a company; they are going to be part of another problem that in Mexico happens: the chief is an dumb-ass and his workers are people with good level, but who don't want to improve their status.

It is well known that our current public system doesn't empaphize in teaching how to think, but how to repeat _and_ do the things your chief ordered to you.

One important person told me that our *president* Fox (the most bizarre political you could ever known) decreased the amount of money for public universities, and since he couldn't do that, he then gave that money to private ones. WHAAAAAAT?

Covariance and Contravariance

2004-12-03T01:58:00.000-06:00

Support for delegates Contravariance/Contravariance support is now in Mono SVN repository.

In C# world, delegates are constructions designed to save a function; in the C world, this is similar to function pointers. Delegates offer some advntages over C function pointers, as compile and run type checks, additional properties, and they also add clearness in code.

Currently, the delegates are defined just as the following example:


 public delegate void MethodHandler (string msg);

In this case, MethodHandler will act as a pointer to methods with the signature defined by itself; this is, methods with void as return value, and string as a unique paratemer. A method such void SomeMethod (string msg) would be valid, but a one like void OtherMethod (string msg, string msg2) or int AnotherOne (string msg) wouldn't.

The problem here is that the methods passed to the delegates must have the exact signature defined by it. Here is where Contravariance and Covariance come to scene.

Covariance
Having something like:


 class A {}

 class B : A {}



 delegate A MethodHandler () { // Do something }

It would be nice to have the chance to pass not only methods like A MyMethod (), but also B MyOtherMethod. This would be possible because Be is just only a specialization of class A, which is the return value defined by delegate MethodHandler. So, returning B instead of A could be done just because B is in fact, a A class, bust maybe with more methods, more properties, etc.

With the Mono 1.x series,a dn also with MS .Net 1.0, that wouldn't be possible. Mo more: .Net 2.0 (which is in state of beta) and current Mono development branch support it.

Contravariance
Again, having code like this:


 class A {}

 class B : A {}

 delegate void MethodHandler (B b);

Methods in the form: void SomeMethod (A a) and also void OtherMethod (B b) could be passed. Why? it's because B instances could be casted to A, so, if a delegate is called, it will receive a B instance, which will cast to A for the void OtherMethod (B b).

Just as above, this is not possible with Mono 1.x/.Net 1.0, but it is avalaible with .Net 2.0 and Mono development branch.

Invitation to avoid your daily lecture of a pseudo portal

2004-11-21T04:31:00.000-06:00

Today I had the bad -when I say, I really mean bad- idea of reading some computer related news at a mexican portal -which name beging with "Co" and ends with "día"- just to see how the ideas are going in this country every day. All the things that, as mexicans dislike, are well represented there, and also they are well applied.

In this portal, is is easy to find persons with a bad aperture to new ideas, and the haughty ideas are there the bread of every day.

Nothing easier than go there (as mexican, it's probably you would have read sometime) and begin to read the news and find that almost everyone there don't believe in nothing, not even in the good things or bad ones; they don't think in the logical things or the other. I don't say anymore, because for a smart person, it should be enough.

I only hope that never the 'main' moderatore there contacts me or somehting like that.

And again, this is an invitation to not visit that pseudo portal anymore, and in general, all the portal where only people wanting see the bad things speak. As someone said, "there's no hope for those persons who only see the ugly things in the pretty ones".

Lets just try to make a better world.

Accessor Modifiers in CVS

2004-11-03T17:03:00.000-06:00

The code for accessor modifiers support is -finally- in CVS. I wanted it to e included in the last release that will be taken place tomorrow (the development release, of course). However, as I said before, it is now in CVS in the mcs module.

The accessor modifiers are a new feature part of the C# 2.0 specification, and with it now is possible to add an access modifier -such PUBLIC, PRIVATE, etc- for the accessors -get/set- in the properties.

This is something important in classes where you want to keep some data hidden, and want to have your Property read-only, for example. A very common behavior for a class would be to have, then, your get accessor public, and keep your set accessor protected:


 public int Count {

    get {

       // count is a private int field

       return count;

    }

    protected set {

       // Only protected members will be able to modify Count

       count = value;

    }

 }

With accessor modifiers, there is improvement hiding get or set methods defined by a Property, thus avoiding the need no keep a lot of variables protected.

The rules for applying this are: your access modifier must be more restrictive than the parent, when overriding the accessor must keep the parent access modifier, and that if yor property has only a an accessor (only set or only get) you can't define an access modifier.

With the first, that implies every access modifier must be more restrictive than the parent, it is not possible to have:


 public int Count {

    get {

    }

    //

    // Error: public is not more restrictive than public

    //

    public set {

    }

 }

The second is very obvious, but the third says you can't have a property just only one a accessor that has access modifier:


 public int Count {

    //

    // Error: Property must have both set and get accessors 

    // for applying access modifiers

    //

    protected get {

    }

 }

And finally, a sample:


 using System;



 public class Test {

     string message;



     public Test (string message)

     {

          this.message = message;

     }

     public string Message {

         get {

             return message;

         }

         protected set {

             message = value;

         }

     }



     static void Main ()

     {

         Test t = new Test ("Mono");

         

         // Good, it is possible to access get accessor

         Console.WriteLine (t.Message);



         // Bad, mcs will complain about the access

         // t.Message = "Hey";

     }

 }

C# Generics

2004-10-30T17:47:00.000-05:00

I wrote a paper about how the System.Object based collections (dynamic arrays with different properties) work and something about the performance. It is the beginning of a serie of small articles to show why Generics (Parameterized types) represent a major improvement in the applications.

The first paper is here: Understanding System.Object based Collections.

Linux in first class countries

2004-10-26T15:51:00.000-05:00

Everyday I use to read the news at DW, which is a resource of news provided by the known german channel 'Deustche Welle'. I'm happy to see a new that says something that a lot of people already knew, but others didn't: Linux is being used more and more, and is used in important cities like Paris and Munich.

The new -in spanish- here.

We are Hackers!!!

2004-10-25T18:39:00.000-05:00

Today in the afternoon I had chance to go to computer event, where the most interesting conference was given by a man working at a enterprise dedicated to the design of websites. They pointed out lot of very interesting facts, and also gave me the opportunity to figure out others.

The man I'm talking about talked about how important the design of a website was. One of the most important things is how easy for an user results. Imagine a site that has a lot of information, and that that site has also a bad organization. Even having a huge amount of information, it's sure the site won't success, because for the user it can represent a bad experience.

He talked they analyse the site they are going to work on, and check for a lot of variables, such: information arrangement, design, they way the page behaves when a resize is done, etc.

Other interesting thing he pointed out was that it's possible to invest a lot of money in your site, but if for example, you don't let the user know the current url, you are wasting that money. Finally, that the marketing was a big aspect to be take care of, just as defining waht you want to do with your site.

We are just simple workers
Maybe the most important thing he mentioned -that is not part of the design of a site-, is that they only design the site, and then they hire somebody to do the work -this is, the coding-. However, he mentioned this in a way in which I could feel he talked about the coders/hackers as simple workers, who don't need to be well paid. What???????

But it is natural, because in Mexico there's no big advance in the computer area. I mean, we don't have big corporations yet, which helps the money-people to think we don't are that qualified people. Add the fact that lot of coders and hackers sell their work so cheap, because of the mexican economical status, and we have a really bad situation. The way in which the man talked about the hackers -almost as people who do bad design- helped me to understand it. Let's face it: the good hackers trend to be bad designers. But maybe that needs to change.

The importance of the design
The first important conclusion is that the design must be planned. Define your target, define who will use your software. Think about its needs. Thinks about the simpleness. Thinks about the colors. Think in everything you can. This will definitely help your product to achieve a bigger step in quality.

I just can about it following the Gnome project ideas: be as possible as you can, but not _that_ simple. You must have a usability guide, you must have in mind what your customers want.

Paste the money and the science
At least something in Mexico happens is that there is a big problem in the way the money is paid. It looks that the current politics of our president -Vicente Fox, who is part of the PAN political group, an extrem conservativ one- are the same we have had for lot of time: the richs get the more, and the poors the less. That's it all resume din that phrase.

The difference could be done by the people hiring and having corporations -even small ones-, who could give their workers a better salary. Guess what? almost NOBODY does it. Isn't it really bad?

I really think a good thing could be having a corporation -a computers related one- where you are also a coder/hacker and _know_ that your workers worth. You don't explode them, you get the money -the money you really need, not more, not less- and stop thinking that the informatic people must not be well paided.

For example, for the example of the corporation dedicated to the design of the sites, you could have in your same corp both the areas dedicated to design and dedicated to the coding. I'm pretty sure you will have a better way to optimize your designs with your coding areas. Isn't that a good idea?

Economical status?
I think that one of the results of our current economical system is this: everyone out there is thinking in how to gain more and more money. In a world where everything is money, you can't escape this trend. I whish that other economical system were possible -and not just a dream-. Maybe, and just maybe we could spend more time in other aspects of our live: social, human, arts.

But we are not, and the best we can do is compete.

Conclusion
Ok, maybe nothing that productive can be gotten from this -it takes so much time and studies-, but somebody could right now begin a corporation that designs precious sites and also codes them. You will have opportunities to give a better way of live to your workers -not just, maybe, the people who graduates from a private university-. As least in Mexico, that's the way the things work.

Patents ...

2004-10-08T01:01:00.000-05:00

I'm very sick about the current patents system. The most known problem with the patents began, I think, with SCO reclaming intelectual properties over Linux kernel, or at least it marked the beginning of the moment we are living currently: the era where you suit the man selling magazines in the street, cause you have the patent number 999999999-565656 that reclaimg the right to sell magazines in the streets.

Probably I should patent the process by which human reproduce themselves - I call call it 'sex'.

The last stupid new I heard of, was a
suit by which Kodak is reclaiming 'a method by which a program can ask for help from another program', which is totally stupid.

Is this the era where everyone suits everyones, as I just states before? It looks like a bad business practice, more than a good one.

Mono Days

2004-09-26T06:07:00.000-05:00

Last thursday I met Miguel de Icaza at Mexico city, where he gave a conference about the advantges of the use of Linux (and particularly the Novell version) over the use of other OS.

His conference was part of a small Novell and Hp event surrounding Linux, and the mentioned event took place at a luxurious hotel where a lot of people had chance to talk to Miguel not only about computers, but abou politics and economics.

After the event we had lunch and I could met also Mancha, Cesar Octavio López Nataren ( the Mono JScript guy) and other Miguel's friends.

Just as always, I must say that I admire Miguel a lot and I'm happy to being working in the same project with him.

Properties Access Modifiers
Currently I'm implementing a new feature that is part of the C# 2.0 specs is the posibility to have your properties accessors with different access scopes. Today, a property is declared as follows:


 public int Property {

      get {

         return val;

      }

      set {

         val = value;

      }

 }

This generates two methods, set_Property and also get_Property, that work very smoothly. It is important to note that both methods will inherit all the acess modifiers indicated in th Property declaration, so in the previous example the methods would be described as:


      public int get_Property ( );

      public void set_Property (int value);

However, sometimes it would be great if the methods need to have different acess modifiers each one. For example, when you have an abstract class that exposes both get and set accessors, but want to declare the get as public, and the set as protected (thus reserved to the subclasses), wou will have to avoid declaring the set accessor and expose it in another way.

With this new feature found int C# 2.0, no more problems of this kind. Now is possible to declared one of the two accessors with different access modifier than the Property itself:


 public int Property {

      get {

         return val;

      }

      protected set {

         val = value;

      }

 }

Finally, the accessors methods would be described then as:


      public int get_Property ( );

      protected void set_Property (int value);

Which will be clearer and prettier than before.

The Geek cliché

2004-09-06T01:01:00.000-05:00

I was reading a blog from a guy who is a geek (almost everybody blogging can be considered a geek), and then found little details that have helped to build the geek cliché, this is, all the things that all the people think a geek does. So I here enumerate them:

Read a lot of trash in the web

A huge huge huge huge ego

Dislike about the stupid society

Have an open source hero ...

... talk tooooooo much about that hero

Talk about the online communities they are in

Hatting trolls but they themselves are trolls

Doing nothing for the community

* Fortunately I hadn't to see him in person, when he missed a Linux event in which I was.

Of course these are only the *features* a geek has while he's online. Is that a lie or not?

System Tune

2004-09-04T06:03:00.000-05:00

Hell! I was preparing me to go to Xalapa today but ... yes, I forgot I had no money, and also that I'm in conflicts with my parents, so go figure out. Shit.

And trying to improve the performance on my almos dead pc (Celereon 500, 256 ram, 40 gb hd), I has to compile-the-linux-kernel, which took me almost 3 hours. And the system is just as slow as before. After checking the system performance, I saw that xmms was using almost 10% of the cpu! And that's just the mp3 player, that is a small application. Now think in Evolution, in Epiphany (because God, I don't use Mozilla), in all the open Terminals, in Gaim, in Xchat ...

The worst is that I could see that alsa is not as slow as before (when it was not included in the linux kernel officially), but it still is toooooo slow. Check the part of the report:

  

 NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND

 0 63316 7500  11m S 10.3  3.3   3:15.13 xmms

 0  1820  816 1620 R  8.6  0.4   0:00.11 top

 0 96076  27m  72m R  6.9 12.3   5:09.98 X

My God, I need a new pc.

Excuses for Federico
I know this is the second time I'm not able to go to Xalapa, and I must confess to be embarrased. I promise to send you the C# book with Mauricio (I know I will see you at irc, but just wanted to make clear that I'm very sorry about this situation).

Officially a Hacker

2004-09-01T23:15:00.000-05:00

Today I commited System.Collections.Generic.Collection class, which is part of the generics support for Parametric Polymorphism in Mono. So, I can say that after sending some small patches, and now this class, I'm a Mono hacker. Now, it's time to go beyond and work on the left classes and then work at the Generational garbage collection support.

Little sample:


using System;

using System.Collections.Generic;



 public class Test {

    public static void Main ()

    {

        Collection <int> c = new Collection <int> ();

        c.Add (3);

        c.Add (5);

        c.Add (11);



        // Note that unboxing is not neccessary

        int sum = 0;

        for (int i = 0; i < c.Count; i++)

              sum += c [i];



        Console.WriteLine (sum);



    }

 }

Compile with gmcs. Enjoy.

6 Invitations to gmail.com

2004-08-31T02:09:00.001-05:00

Today when I opened my gmail's inbox, the first thing I saw was the text in red, saying "Invite 6 friends to gmail.com". Currently, almost all the people I know has already an account. Furthermore, almost all my friends hate internet, which is a bad thing. I wonder if they will be deleted or what.

Collection class finished
After two days without work station, and after a day in which I was totally sick, I could check for compatibility for this class with the .Net implementatiion. It looks like everything is ok, and all my tests were good. However, with gmcs I still can't compile -I still wonder why-.

Probably I will be committing to cvs tomorrow.

Bad, bad, bad

2004-08-20T05:11:00.000-05:00

Ok, ok, I know, Mexico is not having a good time at Olympic Games. We could say that it is because of the government, the social problems, and things like that. And in fact, the could all be true. But for me, that represents the big, huge, importance of preparing yourself for your objectives. That's all. If you know your rivals are as twice strong as you, then you must go and get four times the potential you have.

Yesterda I heard at a tv show that the "heroes" from Mexico had arriven to Greece. Well, they lose one or two hours ago. Pretty bad. And it is very sad to observe that lot of people representing Mexico at the OG needed to train themselves for 4 years, every day, having to work, or to study. Now, imagine you are one of them, and that a small mistake makes you lose in your are. Bad, isn't it?

The most important thing is that all those persons that have to work harder and harder every day to do anything (sport, coding, etc) is that they must train and go to their limits from day to day. That's the only way I can imagine it.

Congratulations to those persons that go to OG and had to lose again the best of the best in this world. Increible that we still have people who can go beyond with almost nothing support by the government and its departments. Let's go, people!

A little paper about GC
Garbage collections is the routine of managing the memory in a certain environment. Maurimal (Mauricio's friendly name) got an excelent paper about GC here. Now I will have something to play with until I wait for that-gc-book-you-have-heard-about. Thanks Maurimal, you are my hero.

Linux event
Here in Puebla a Linux event will take place in the next month. It is an event ths is done yearlyby the Linux user group from Puebla and that intends to show to the people the big big power of Linux and the Open Source software.

Currently a call for papers is having place right now, so, if you think you have something to say, and something that someone should hear, then, send your paper!

I hope to see people from different universities in that event. If everything goes well, we will have Arturo Aldama Espinoza, Mancha, Gunnar Wolf and Federico. More info can be found here.

Generics and more generics

2004-08-18T04:01:00.000-05:00

While waiting for the GC Book Federico will lend me in a marvelous action, I'm working at Generics, a new feature that will be part of the Mono 1.2 release for next february and that will have compatibility with the .Net 2.0 from MS.

Currently I'm working implementing some classes in the System.Collections.Generic, specially in the Collection class, that it is designed to be the base for custom classes that need to keep a collection of objects, thus avoiding writing a new collection class from scratch. It is a small and easey-to-implement class, however, this is a great chance to code Generics and learn a lot of them. I highly recommend the document in the Generics site to understan the way they work and the internals to make this feature happen.

Some notes about Generics
There may be some people who doesn't want to go and read that paper, because of its complexity or because its size. For them, some notes about thus new feature called Generics, or Parametric Polymorphism.

Currently the collection classes (Stack, Queue, ArrayList, etc) use System.Object as a wrapper for the data (this could be the equivalent to void* in C world, but not exactly the same). However, this impact a lot in performance, beacuse when you use reference-based variables (instance classes, e.g. System.String), the runtime will have to 'wrap' your variable. Something worse happen with value-based variables (e.g. System.Int, System.Long, System.Enum, etc), because they originally live in an area called 'runtime stack', that make them very light, and thus casting them to be of type System.Object will create a reference-based variable, using more innecessary space and also creating an almos useless additional variable.

Then, when a value based variable is passed as argument for a method, it will be automatically casted and impact performance. When an instance class is passed, the impact will be smaller, but it will exists. Obviously, this can cause some coders to re-implement a custom collection class.

Because of that, Parametric Polymorphism exists. It is a feature similar to those 'templates' in C++ world (note that I'm not a C++ guru). As far as I know, templates is a mechanism similar to macros in C world, but better. Now, imagine you can use the capabilites of the CLI (Just-In-Time compilation, Metadata, etc), and then you will have an interesting design, creating custom classes based on the 'generic' class. So, everytime a class is requested, the runtime will check for it: if it previously exists, it will re-take the stubs; if not, it will create it.

Imagine the code:


 class GenericClass <T> {

     int Add (T item) {

       ...

     }

 }

Observe the new parameter, ''. The 'T' will be an alias for the types passed in the creation of the new class. This alias will be used along all the class definition and then will generate it depending on the type. For example, you could declare it as:


  GenericClass <int> gclass = new GenericClass <int> ();

  ...

  Add (6);

The above code will be valid, because the int type will be used as the base class,
having emitted code like:


  int Add (int item) {...

Im my opinion, this is a great feature, and I recommend again the lecture of the paper that is on the Generics site.

Bad Days

2004-08-09T19:08:00.000-05:00

There are days when you you so much problems that you can't believe it. Well, I'm in those days: my cpu got broken, my internet connection was having trouble the entire day, I couldn't go to see Federico last Saturday ... I only hope to have less problems in the next days ...

Generics

Finnaly done with the Generics Paper Lecture. It is very impressive that a lot of ideas behind it are a little old, and the way they were taken. Now I think I'm ready to begin implement some classes and test for the .Net 1.2 compatible Mono release (expected in next february).

Also, I can't wait to see Federico and read that Richard Jones' GC book. I hope to be at Xalapa next weekend or something like that ...

I need a GC Book

2004-07-19T23:57:00.000-05:00

Today I spent almost all the day trying to build some samples with both the conservative Boehm and the Electrical Fire's generational garbage collectors. With the first, which is conservative and uses a mark and sweep algorithm, I could do a small example and looks easy to use. With the second (the one from the Electrical fire project) I couldn't build it, because of the old and bad Make files (it looks like they are not updated).

However, the papers I've found on google don't satisfy me, and I'm thinking I should buy a book about GC written by Richard Jones. So, if you want to contribute, you can give $ 0.1 and with 800 person helping me I will be able to buy that book ;-).

Avoiding showing errors is bad

2004-07-16T16:28:00.000-05:00

I have just finished installing Fedora Core 2 and well, just running some problems (ntfs support, usb ports, etc). But the biggest problem is that I still can't run the graphical mode, adn worse, I don't get error messages.

In some manner, it is normal in software to have some problems. But, what about showing good errors? In my opinion, good error messages can really help to know where the error is. Bad error messages can help, but maybe they won't give you enough information. Finally, if you are only giving some messages to some errors, well, then the problems for the user will be wrong.

Finally, I would like to say that I've been receiving a huge amount of critics. It used to be good when I only receive critics (and most importan, constructives ones) when asked for them. But, what about when you receive them without asking for them? And the worst of all, it's when you got critics about things that all the persons do every minute. Advantes of living in an exotic country like Mexico is.

Garbage Collection in the .Net Framework

2004-07-08T02:21:00.000-05:00

Some time ago I was reading some papers about Garbage Collection, which is the process of managing the allocations and deallocations of memory in an environment. Unfortunately, that information is hard to find in the web, since only some little info or slides are avalaible (I found an interesting book at amazon about GC, but it is so expensive).

Since that, I'm trying to read that little info, and since I could access the ACM digital library, I'm going to check some related papers. However, I have the experience that this kind of papers only cover the theorical part, and thus are not enough for me (I have more than a just theorical interest on GC).

However, I found good papers in the MSDN site and currently I'm reading the GC internal. Those papers are interesant, but again, they do not cover the area I'm interesting in (of course that I'm interested in the area they cover, it is just that I need some more information).

Something very interesant is a process called Resurrection, by which a dead object (unreachable and thus marked for being deleted from the memory) can be resurrected. Imagine you have an object that has a Finalizer method (destructor syntaxis in C#) that assigns a global/static variable a pointer to your current object:

~MyClass ()
{
// 'this' refers to the current instance
MyNamespace.AnyClass.AnStaticObject = this;
}

When and object has a Finalizer (destructor in C#), is added to an internal GC data structure called F-Reachable queue, that contains pointers to object that need to be finalized before they get deleted. However, if you have something like the previous code, your object will live again, but its Finalize method won't be called when it becomes -again- unreachable.

In fact, resurrection should NEVER happen. Just for the purpose of 'security', if the object needs to be finalized, an internal boolean flag could be added, keeping the state (finalized or not) and throw an expection when a method is called (throwing an expeption from the Finalizer would only finish the method).

I need to move to Fedora

2004-06-23T23:16:00.000-05:00

I've been haing some trouble with RH 9 and the ext3 file system. Some time ago I tested Mandrake and ReiserFS and it worked very smooth, without problems. Now I'm using ext3 and I hate the way it 'locks' my files (I have to reboot). And based on tha benchmarks, I'm really waiting for Mono 1.0 core release to move to Fedora Core 2 (I was thinking about Debian; however, its comunity scares me a lot).

Germany out of the Euro

Very bad. Germany is out of the Euro 2004 and I'm very sad about that, but I hope this makes understand Rudi Völler that his 4-5-1 is bad and inefficient. Lets have better hopes for World Cup. Now, my favorites are Holland, England and, of course, France.

Futbol!!!!

Recently my friend Jorge Carrasco wanted me to look for a place to play soccer. I have invited some old friends and tomorrow we will be playing. I have a lot of time without playing, and now it's a good time to re-take it.

Euro 2004 & other stuff

2004-06-16T02:19:00.000-05:00

The Euro 2004 continues and I'm just seeing that geeks don't like soccer (very bad). Today was the game Germany vs Holland, and I think it was a good game (however, in a lot of sites the press is not comfortable with that opinion). The best of the game: Michael Ballack from Germany and -of course- Van Nistelrooy -is that well written?- from Holland. No more need to be said.

At Carrasco's house

Today I was almost all the day with my friend Jorge Carrasco -who is a lawyer and we met at school when we both were 14 years old- and we were talking and thinking about the behavior of the people around us. Very interesting, and I must say I needed to talk to someone who weren't a geek or a computer.

Port of Rhino

I continue with the port of the lexer and parser routines from the Rhino engine. Today I could in a pair of hours check some errors in the Lexer and I hope to finish tomorrow or maybe on thursday it and go to the parser. No challenge, but it must be done by someone.

Books, books, books

I was reading danguer's blog and I read there that he has just finished reading The Illiad. I must confess I'm jealous because I don't have so much oportunities to read a book, and I must just wait for any chance to get a new one. The last I got was a Lovecraft book about horror stories and was good. But I bought that book 1 or 2 years ago, so try to figure out why I need a new book. It looks like danguer has stopping reading pseudo philosophical books, which is a good thing. I'm still trying to understand why geeks can't just support the idea that another geek read as much as you (hey! I'm just jealous about that I can't read so much books as I wished). Y have geek pals that still think that I'm not just as good as they at culture.

Yes, this is my selfconfidence moment of the day and ... Yes, I think I have a much higher culture level that most of the geeks I know. No more needs to be said.

Why the geeks need to stopping being geeks?

2004-06-14T23:46:00.000-05:00

Yesterday and part of this day I¡ve been thinking about the fact that a lof of computer people -admins, coders- are known as geeks, which turns to be a word to describe people who don't like to have real-life friends, read a lot, and so on. The difference, as I see it, between a nerd and a geek, is that the geek doesn't go to cinema, doesn't go to take a break, doesn't play sports, and also doesn't like to dress cool. Also they have to be fan of facism (with this I try to say that they are persons who only believe in their ideas and no more, and don't like to listen different opinions).

A nerd, on the other hand, is just a person who dedicates great amount of time trying to finish a task and no more. He/She is not an expert, which is really bad. But the nerd trends to be a average person.

I'm not trying to say that being an average person is the best, but I think that, if you can't control your feelings and you feel like an outsider, you should better be an average guy.

The problem which lots of geeks is that they are all the day complaining about the society and every thing in the planet. The cars, the money, and the way of life. That's not bad, as it could be just be tranfered into social critics. But wait, a geek, just as the ones I one, whould always be complaining _and_ feeling miserable about that. Then they began to hear bad music, to watch sad movies and so on. The live in a depression built by themselves, which is horrible.

Since a lot of work needs to be done in front of a monitor, a lot of geeks lose social life. The question, however, is: do they lose social life because of the work, or because of the fear to the society? I'm very sure that ALL of them would say that they like to code/admin better than going out with friends. But let me say something: I really think most of thems are afraid of the extern world, that one that lives outside a computer, in the streets, in the cinemas, in the malls, in the sport centers.

We could find two vertients as a possible cause of this: the first, is the bad way of being of the person and thus avoiding any form of social contact. The second, is an anormality in the society that together with discrimination will create persons like that.

have you heard about persons who doesn't like to go out? I'm sure you have listened of those people. Yes, serial killers.

Please, stop being a geek, change the way you think, and be more respectful of other ways of thinking. Go to the cinema on saturday, get yourself a lover and play some sport -even if you aren't good at-. Search for friends that are not that geek. Feel much better, and please avoid being a serial killer or even a guy who only lives for sadness and alcohol/drugs. Make yourself a favor and help to build a better world.

Stop thinking you are THE correct and the world is wrong. Stop thinking you are superman.

Some notes on weekend

2004-06-13T20:40:00.000-05:00

I'm a little bored right now -sunday evening-, and while my parents are watching tv -thus I can't see it-, I'm trying to see what to do, but without needing my brain. Hey, it's a sunday!

Wow, France!

Today I saw the France vs England game, and wow. I must confess I was very sad at the end of the game, because England was winning 1-0, but then that sadness became happiness after the only one Zinedine Zidane made two goals. Great!!! (I want to avoid the comment on the game that Pumas won versus Chivas, the mexican national soccer final). For tomorrow: Italy vs Denmark. I really would be a geek is I had nothing to do but only coding ;-)

.NET Blogs

I was curiois about the note I saw on a Mono blog -I don't remember who wrote it-, that made reference to the .NET guys at Microsoft. So I wen to MSDN and looked for them ... Now, I have the address and another resource for learning:

Brad Abrams - Guidelines

Maoni's Weblog- Performance

CBrummes's Weblog - Misc topics

Reflection Emit and Parametric Polimorphism Stuff

2004-06-12T00:39:00.000-05:00

WOW! Finally the Euro 2004 is here! The best soccer of the all f*ck world! No more mexican trash .... ehr I mean, no more mexican soccer. My teams? Germany, Italy and Holland. No more. One of this must be the champion. The final must be decided between Portugal and Germany, with Portugal as champion, so we can have a beautiful world champion: the semi-final between Germany and Portugal (the first revenge) and the final between Germany and Brasil (the second revenge). World Champion for 2006: Germany. (Note that I'm a big fan of Germany and currently I'm planning to go to study the university there).

Reflection Emit

Yesterday I sent my patch for support to EnumBuilder class to the mono-devel list. Now it is going to be possible to use that class to emit the IL for en enum, avoiding the use of TypeBuilder and that stuff ...

However, I note that it is not that hard to emit an enum (you only need to know some things about the internals of the CLI architecture). But since a lot of people are not wanting to know the internals, I think it could help them and could help to keep a clearer approach.

Thus currently to build an Enum using RE you should type:

EnumBuilder enumBuilder = new EnumBuilder ("enumName",
TypeFlags visibility, Type typeoftheEnum);
//Define some values for this enum
enumBuilder.DefineLiteral ("FirstValue", 0);
enumBuilder.DefineLiteral ("Secondvalue, 1");
enumBuilder.CreateType ();

And an enum enumName {Firstvalue, SecondValue} will be created.

Parametric Polimorphism

I was reading the first six pages of this document about generics found at Microsoft UK Research, describing a feature called Parametric Polymorphism that let the CLI to emit collections (just an ArrayList or HashTable) for a certain type, and not anymore for a generalized System.Object. This is great.

Rhino Parser and Lexer Port

I'm working in the port of Java implementation of Javascript, Rhino, that is part of Mozilla Project, to C#, thus we can use it on Mono to build the JScript compiler (by Cesar Lopez Nataren). It doesn't represent any challengue and should be finished by a week or two.

The best and the worst

The best: my friend Mauricio printed for the the Ecma 334 standard! Cool. The worst: the project DotGnu and its FUD (the begin by saying that Mono has spreaded some FUD, and continue saying bad things in his homepage). It even doesn't deserve to be mentiones anymore.

Emitting IL and other stuff

2004-06-07T20:05:00.000-05:00

I've been adding some research about the IL doing some research about the IL doing some research about the IL basics on Mono, and I just got working the creation of the IL for a Enum using System.Reflection. The problem about my latest approaches was the fact that a special field called value__ must be added to the class.

Based on that, I'll be coding the System.Reflection.Emit.EnumBuilder class. I don't think is will represent a challenge, and the only important thing will be compatibility with .NET.

Also I was reading about parametric polymorphism (aka generics), that represent an interesting approach to the collections that Mono/.NET currently support. The fact behind this feature of C# 2.0 is the posibility of having dynamic collections, like a Stack or a Queue, of the exact desired type. Thus you won't have to use objects as the fundamental unit, avoiding the runtime casts (that cause a lot of runtime related problems and hard to catch).

I will be writing two articles: more about p/invoke, and other about GC in Mono (and good practices).

Finally, right now I'm taking a break with Mauricio. Cool.

Why I love C# (and Mono)

2004-06-03T23:37:00.000-05:00

Mi idea about creating this new blog (and of course, based on the fact that mi last blog server is offline) was caused by the title of the first post of danguer, who has a entry standing for "Why I love Python".

Before all, I must say that I confess that I think he is talking about python just as a platform, and not just like the language itself.

Said those things, let's start: I really really love the idea behinf the Mono Platform because of some simple things:

Multiplatform capabilites

Support for Multiple languages

Great API

Freedom

and ... performance

Currently in Mono we have support for BasicNET (renames as MonoBasic) and for C#, the most beautiful language I have ever seen. It mixed the best of Java/VB/C++. Can you imagine that! That's so much POWER!

First of all, I don't have to see the horrible event model in Java (we have delegates, a powerful way to encapsulate methods and results to be type safe). Also, I don't have to play with weak-type languages like perl or python or basic or ... I really like the clean things and couldn't support to have such an inefficient app that needs that bad approach. Really.

Second, I like the way it is performing the inheritance, and the way it drives the default scope of the members of the class. A big difference with MonoBasic.

Third, I like new statements that add great capabilities. For example, we have the using keyword/statement, that lets use a resource for a limited scope, hiding psoiible problems durin its execution. You will find it useful in a lot of scenarios in which you don't want to write the awful try/catch statements.

This should be enough. Some other things I could say would rely on the Mono platform. However, I think could show the difference between liking a language and a platform.