Re: [Vala] Parallel programming in Vala?
From: Costas Smaragdakis kesma...@gmail.com Sent: Tuesday, 27 May 2014, 13:50 Subject: Re: [Vala] Parallel programming in Vala? I would like to share the processes on multiple computers through typical network. If you want a distributed computing environment then Hadoop may be worth considering. It seems to be in demand at the moment so may help with a post-doctorate job too! Hadoop is distributed file system and Java based distributed process control system. Hadoop also has a process called streaming that allows data to be processed by arbitrary binaries and scripts, and this could include Vala produced binaries. Not sure how this fits into Hadoop2 though, but a few links that I have bookmarked: http://wiki.apache.org/hadoop/HadoopStreaming http://www.glennklockwood.com/di/hadoop-streaming.php Some comments on its application to scientific computing: http://hortonworks.com/blog/hadoop-in-perspective-systems-for-scientific-computing/ http://www.slideshare.net/hortonworks/large-scale-math-with-hadoop-mapreduce And at the really rough edge you could even try GPU computing nodes with OpenCL and Vala: http://www.slideshare.net/DevCentralAMD/is-4011-zubindowlaty http://dummdida.blogspot.co.uk/2011/11/wrapping-opencl-with-vala.html https://gitorious.org/valastuff/vapis/source/d879797216778030f3a281f6d27d157c7fa1f76d:vapis/OpenCL.vapi http://blogs.igalia.com/elima/2013/05/06/introducing-gocl-a-gobject-wrapper-to-opencl/ https://github.com/elima/gocl If you ever do this, then a blog post to the world would be very interesting on how far you got. Al ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
Re: [Vala] A brand new build system
From: Robert Ancell robert.anc...@gmail.com To: Steven Oliver oliver.ste...@gmail.com Cc: vala-list@gnome.org vala-list@gnome.org Sent: Friday, 16 May 2014, 22:43 Subject: Re: [Vala] A brand new build system (I'm the author of Bake). Bake has detailed documentation with it (as shown in that link) The documentation is also readable in raw Mallard format (much the same as HTML): http://bazaar.launchpad.net/~bake-team/bake/trunk/files/head:/help/ It give me the impression Bake is intended to be comprehensive :-) and the Vala page ( http://bazaar.launchpad.net/~bake-team/bake/trunk/view/head:/help/vala.page ) might be worth a look. So it's held in Bazaar, any thoughts on switching to Git? Eric S. Raymond argues Bazaar is dying ( https://lists.gnu.org/archive/html/emacs-devel/2014-01/msg5.html ). You might get more people giving it a quick spin if they can do a git clone. I was about to give it a go, but only got as far as reading this ( http://askubuntu.com/questions/10389/how-can-i-import-bzr-branches-into-git ). but lacks a website [1]. Help welcome :) [1] https://bugs.launchpad.net/bake/+bug/1215366 What kind of website? I presume the project infrastructure, i.e. repository, mailing list, bug reporting will be handled off site? How would you describe the current status of the project and its goals in a hundred words? :-) Looks a very interesting project. NEWS file also gives a flavour ( http://bazaar.launchpad.net/~bake-team/bake/trunk/view/head:/NEWS ) All the best, Al ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
Re: [Vala] Memory safety
Vala inherits the problem of C, yes. You could certainly do some evil
casts like in C. Vala however is certainly safer than C in many aspects,
in other aspects however you have to know what you are doing and how
Vala compiles down to C in certain cases.
Okay, good to know. I asked because some of the offset/lengths check in
the glib string library are a bit … off, and they can trigger C integer
overflow, which is undefined. But if Vala is general unsafe in this
sense, it may not be necessary to fix these instances (it would be
painful anyway because this code isn't in a dynamically linked).
--
Florian Weimer / Red Hat Product Security Team
Is there a bug report for this with more details?
I would say in general Vala/Genie attempts to be safer than C, within the
limits of a language that compiles to C code.
Vala strings are UTF8 encoded gchar, but the length and indices are in bytes.
See https://wiki.gnome.org/Projects/Vala/StringSample
A program such as:
void main () {
string a = hello;
char b = a[100];
print ( b.to_string() );
print ( ((int) b).to_string());
}
will compile and the C code generated uses the line
_tmp1_ = string_get (a, (glong) 100);
to get the index. I'm not sure where string_get function comes from, but the
output is a zero byte for an out of range index.
The GLib string builder function (
http://references.valadoc.org/#!api=glib-2.0/GLib.StringBuilder ) is also
recommended for use in Vala.
So I think your question raises some interesting questions about how Vala
programmers should handle strings securely to avoid buffer and integer
overflows for a robust application. It would be nice to gather some ideas on
this. Maybe for starters http://www.and.org/vstr/security
Regards,
Al Thomas
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[Vala] Recommended way for combined C with Vala/Genie project?
I've just got this error that made me wonder about valac's hidden capabilities: error: test.g is not a supported source file type. Only .vala, .vapi, .gs, and .c files are supported. I assume a .c file is passed straight through to the C compiler along with the generated C files from .vala and .gs files. Is this a recommended way of creating a combined C with Vala/Genie project? I note XFCE decided to combine C with Vala. From a couple of blog post [1][2] it looks as though they use automake to create C files from Vala and then distribute and compile those files for the whole project. The argument being different versions of valac can produce different C files so it is more stable for a distributed version to build from the generated C files. I also found the Parallel Builds [3] page. This is an interesting approach with, as I understand it, an intermediate object file for each vala file. These could be linked with object files from C or C++. Then there is the --compile option of valac to produce object files. So at the moment I'm thinking for large, mixed language projects, it is better to create object files and link outside of valac. I am writing some documentation for Genie and was about to finish the attached diagram with arrows when I stumbled upon valac accepting .c files. At present I'm thinking this feature isn't too useful and it is better to create object files and link using another tool. This is also useful for GIR and using Vala/Genie binaries in Python, node.js, PHP, etc. So it is probably better for documentation to introduce the more general process. Thanks for any thoughts. Al Thomas 1 - http://blog.m8t.in/2009/09/build-project-with-vala.html 2 - http://blog.m8t.in/2009/12/messing-up-with-vala-again.html 3 - https://wiki.gnome.org/Projects/Vala/Documentation/ParallelBuilds ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
[Vala] [Genie] Re: Vala on Android
Great stuff Gontzal! Does this mean Vala/Genie programs can be compiled for non-rooted Android devices? I have created a new Genie wiki page: https://wiki.gnome.org/Projects/Genie/TutorialsBlogsExamples and included links to some of your projects and tutorials. I have also included a link to https://github.com/avalanche-games/avalanche/wiki/Getting-Started-%28for-Linux-users%29 to help get people interested in this. What do you think? Al From: gontzal txasato...@gmail.com To: vala-list@gnome.org Sent: Saturday, 15 March 2014, 0:01 Subject: [Vala] Vala on Android Hi Folks!! Genie is already runing on Android using SDL 2.0. See an educational app in android playstore named Katamotz Hitzak . How to compile a genie/vala + SDL 2.0 game-application? http://manualgenie.blogspot.com.es/ https://github.com/avalanche-games/avalanche/wiki/_pages thanks... i love Genie. Maintain it please ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
Re: [Vala] How to convert a string to float ?
From: r...@no-log.org r...@no-log.org To: vala-list@gnome.org Sent: Tuesday, 24 September 2013, 13:36 Subject: [Vala] How to convert a string to float ? To convert a string to int : int.parse ok, easy... Try double.parse() For more see https://wiki.gnome.org/Vala/Tutorial#Strings Al ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
[Vala] Fw: Extra documentation for vapis on Valadoc
From: Steven Oliver oliver.ste...@gmail.com To: vala-list vala-list@gnome.org Sent: Tuesday, 24 September 2013, 19:15 Subject: [Vala] Extra documentation for vapis on Valadoc My question is how did the extra documentation get there? I looked in the Glib-2.0 vapi but there's nothing extra there. My understanding is Valadoc is not generated from vapi files. It has it's own markup style ( see http://valadoc.org/#!wiki=markup ) and source code ( see https://gitorious.org/valadoc-org/valadoc-org/ ), but that may not be the whole story because the relevant valadoc file I can find ( https://gitorious.org/valadoc-org/valadoc-org/source/6c7d58e17a247438337d75bde80737f0e539fa2b:documentation/glib-2.0/glib-2.0.valadoc ) doesn't seem to contain the GLib.Markup.printf_escaped function you were interested in. Hope that helps, Al ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
Re: [Vala] Worried about the state of Genie
On Thursday, 29 August 2013, 9:53 Tal Liron wrote I like your two suggestions, Al, and hope you will open them as enhancements so at least we can track them. But this discussion on specifics is pointless if no work will be done on Genie! I've logged my two suggested enhancements. Next year I will try and look at implementing them. I think the summary of the wider discussion is that the Vala community are OK with Genie so long as it is useful and maintains to be and that Jamie McCracken has indicated he will try and deal with serious bugs. There is a big gap here and that is the Genie community. I'm going to raise three new threads here to see what response we get. Al P.S. Thanks for sharing the link to your Genie talk. Some useful stuff there. ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
[Vala] [Genie] Print enhancements and handling of null
This is using two Genie bugs as examples to try and find out how the Genie community handle triage, documentation and enhancements. The two more bugs are print statement with no arguments does not compile ( https://bugzilla.gnome.org/show_bug.cgi?id=688016 ) and Print statement does not print newline if it has a null argument ( https://bugzilla.gnome.org/show_bug.cgi?id=690127 ) Print statement with no arguments does not compile --- This is a request that to print a blank line just print can be used, instead of print . This would be like Python 2, although with Python 3 and print now being a function simply typing 'print' returns a statement that it is a built in function. Personally I don't mind if print with no value just prints a blank line instead of returning a compile error. The question is who agrees this change? It is reasonable to have the print statement expect something to print so this is probably more an enhancement than a bug. Is there a Genie benevolent dictator such as with Python or can only a community consensus be agreed for a change to be accepted? How is the acceptance then recorded - presumably in bugzilla? Once the change is agreed, who is assigned the task of fixing it? In this instance because it is a fairly trivial change I think it should be assigned to the raiser, but what if they are not capable of delving into the Vala source code for Genie to fix this? Should this instead be closed as a good idea, but with limited resources there was no-one to take on the task? Once a patch is received in bugzilla how is it reviewed and applied? There is at least one bug ( https://bugzilla.gnome.org/show_bug.cgi?id=633083 ) which has a patch that has not been applied. Print statement does not print newline if it has a null argument I tried to generate some nulls and it made me come across what may be seen as a different bug. var test = new array of int [5] for var item in test print item.to_string() prints all zeros. var test = new array of string [5] for var item in test print item prints all nulls. Would it be better to have this as all empty strings? There is a desire to avoid nulls, for example see https://wiki.gnome.org/Genie#Nullable_Types and https://wiki.gnome.org/Vala/Tutorial#Strict_Non-Null_Mode. Would a new array of strings with empty strings solve the use case the bug reporter was having problems with? If so then can this bug be closed as nulls are ugly so they should probably print ugly! and open a new bug that new array of string [x] should be empty strings not nulls. Otherwise I can't think of any problem with having print null print with a newline, so it leads so the same set of questions as the analysis above. Thoughts? Al ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
Re: [Vala] [Genie] Using async methods in Genie
Alex Stefan Kaye wrote on Saturday, 27 April 2013: Is it possible to use Vala's async methods in Genie? If so, could someone give an example of the syntax to use? I have not used them myself, but have made a few bookmarks when I was researching Genie: https://mail.gnome.org/archives/vala-list/2011-February/msg00072.html - suggests it works and syntax for declaring a function is def async function_name (): https://live.gnome.org/Vala/Tutorial#Asynchronous_Methods - hopefully Genie closely matches the Vala syntax such as the use of the yield keyword Other bookmarks: https://live.gnome.org/Vala/AsyncSamples https://live.gnome.org/Vala/GIOSamples#Asynchronous_File_Listing http://tecnocode.co.uk/2012/12/30/single-thread-synchronisation-in-vala/ https://mail.gnome.org/archives/vala-list/2011-July/msg00111.html If you get it working a short write up of your code would be helpful, Al ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
Re: [Vala] [Genie] Dict/List as properties
On Sun, 14 Apr 2013 20:50:07 +0001, Alex Stefan Kaye noxdeleo googlemail com wrote: I'm wondering if/how I can use dicts and lists in class properties, for example: prop private channel_map:dict of string,list of Gst.ChannelPosition I remember having a similar problem in the one Genie program I've written so far. I don't have an exact solution, but found this worked for an array of strings: class log_hit : Object _fields : array of string[] prop readonly ip_address : string get return _fields[1] construct ( ) _fields = new array of string[10] I found using the _variable_name overcame what is probably a memory corruption bug when I used prop private. Then creating the actual array when the object is constructed works for an array of strings. So you could try something along the lines of: class my_class : Object _channel_map : dict of string, Gst.ChannelPosition construct() _channel_map = new dict of string, Gst.ChannelPosition If this inspires you to find a solution let us know! Also some references on dicts and list: http://bkhome.org/genie/datatypes.htm https://live.gnome.org/Genie#Dicts http://manualgenie.blogspot.co.uk/search/label/03.1%20Listas%20complejas.%20Lista%20de%20objetos. Good luck, Al ___ vala-list mailing list vala-list@gnome.org https://mail.gnome.org/mailman/listinfo/vala-list
