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• GPL'ing code of a third party?

  - by Mark

  I am facing the following dilemma at the moment. I am using code from a scientific paper in a commercial project. So basically I copied and pasted the code from the paper's pdf into my code editor and use it in my own code. The code in the paper does not have any copy restrictions or license(like the GPL) so I thought I would be ok using it in a commercial project. However, I have seen several gpl licensed open source projects that use the exact same code from the paper to the point of having the same variable names like in the paper. So what happened here is that a gpl license was put on a third parties non gpl'ed code. Are these open source projects in violation of the gpl or would I be in violation of the gpl because I use code which has been gpl'ed? My common sense tells me it is not allowed to gpl somebody elses non-gpl'ed (like in this case from the paper) code but I though I would ask anyway.

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• About Solaris 11 and UltraSPARC II/III/IV/IV+

  - by nospam(at)example.com (Joerg Moellenkamp)

  I know that I will get the usual amount of comments like "Oh, Jörg ? you can't be negative about Oracle" for this article. However as usual I want to explain the logic behind my reasoning. Yes ? I know that there is a lot of UltraSPARC III, IV and IV+ gear out there. But there are some very basic questions: Does your application you are currently running on this gear stops running just because you can't run Solaris 11 on it? What is the need to upgrade a system already in production to Solaris 11? I have the impression, that some people think that the systems get useless in the moment Oracle releases Solaris 11. I know that Sun sold UltraSPARC IV+ systems until 2009. The Sun SF490 introduced 2004 for example, that was a Sun SF480 with UltraSPARC IV and later with UltraSPARC IV+. And yes, Sun made some speedbumps. At that time the systems of the UltraSPARC III to IV+ generations were supported on Solaris 8, on Solaris 9 and on Solaris 10. However from my perspective we sold them to customers, which weren't able to migrate to Solaris 10 because they used applications not supported on Solaris 9 or who just didn't wanted to migrate to Solaris 10. Believe it or not ? I personally know two customers that migrated core systems to Solaris 10 in ? well 2008/9. This was especially true when the M3000 was announced in 2008 when it closed the darned single socket gap. It may be different at you site, however that's what I remember about that time when talking with customers. At first: Just because there is no Solaris 11 for UltraSPARC III, IV and IV+, it doesn't mean that Solaris 10 will go away anytime soon. I just want to point you to "Expect Lifetime Support - Hardware and Operating Systems". It states about Premier Support:Maintenance and software upgrades are included for Oracle operating systems and Oracle VM for a minimum of eight years from the general availability date.GA for Solaris 10 was in 2005. Plus 8 years ? 2013 ? at minimum. Then you can still opt for 3 years of "Extended Support" ? 2016 ? at minimum. 2016 your systems purchased in 2009 are 7 years old. Even on systems purchased at the very end of the lifetime of that system generation. That are the rules as written in the linked document. I said minimum The actual dates are even further in the future: Premier Support for Solaris 10 ends in 2015, Extended support ends 2018. Sustaining support ? indefinite. You will find this in the document "Oracle Lifetime Support Policy: Oracle Hardware and Operating Systems".So I don't understand when some people write, that Oracle is less protective about hardware investments than Sun. And for hardware it's the same as with Sun: Service 5 years after EOL as part of Premier Support. I would like to write about a different perspective as well: I have to be a little cautious here, because this is going in the roadmap area, so I will mention the public sources here: John Fowler told last year that we have to expect at at least 3x the single thread performance of T3 for T4. We have 8 cores in T4, as stated by Rick Hetherington. Let's assume for a moment that a T4 core will have the performance of a UltraSPARC core (just to simplify math and not to disclosing anything about the performance, all existing SPARC cores are considered equal). So given this pieces of information, you could consolidate 8 V215, 4 or 8 V245, 2 full blown V445,2 full blown 490, 2 full blown M3000 on a single T4 SPARC processor. The Fowler roadmap prezo talked about 4-socket systems with T4. So 32 V215, 16 to 8 V245, 8 fullblown V445, 8 full blown V490, 8 full blown M3000 in a system image. I think you get the idea. That said, most of the systems we are talking about have already amortized and perhaps it's just time to invest in new systems to yield other advantages like reduced space consumptions, like reduced power consumption, like some of the neat features sun4v gives you, and yes ? reduced number of processor licenses for Oracle and less money for Oracle HW/SW support. As much as I dislike it myself that my own UltraSPARC III and UltraSPARC II based systems won't run on Solaris 11 (and I have quite a few of them in my personal lab), I really think that the impact on production environments will be much less than most people think now. By the way: The reason for this move is a quite significant new feature. I will tell you that it was this feature, when it's out. I assume, telling just a word more could lead to much more time to blog.

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• .NET Security Part 4

  - by Simon Cooper

  Finally, in this series, I am going to cover some of the security issues that can trip you up when using sandboxed appdomains. DISCLAIMER: I am not a security expert, and this is by no means an exhaustive list. If you actually are writing security-critical code, then get a proper security audit of your code by a professional. The examples below are just illustrations of the sort of things that can go wrong. 1. AppDomainSetup.ApplicationBase The most obvious one is the issue covered in the MSDN documentation on creating a sandbox, in step 3 – the sandboxed appdomain has the same ApplicationBase as the controlling appdomain. So let’s explore what happens when they are the same, and an exception is thrown. In the sandboxed assembly, Sandboxed.dll (IPlugin is an interface in a partially-trusted assembly, with a single MethodToDoThings on it): public class UntrustedPlugin : MarshalByRefObject, IPlugin { // implements IPlugin.MethodToDoThings() public void MethodToDoThings() { throw new EvilException(); } } [Serializable] internal class EvilException : Exception { public override string ToString() { // show we have read access to C:\Windows // read the first 5 directories Console.WriteLine("Pwned! Mwuahahah!"); foreach (var d in Directory.EnumerateDirectories(@"C:\Windows").Take(5)) { Console.WriteLine(d.FullName); } return base.ToString(); } } And in the controlling assembly: // what can possibly go wrong? AppDomainSetup appDomainSetup = new AppDomainSetup { ApplicationBase = AppDomain.CurrentDomain.SetupInformation.ApplicationBase } // only grant permissions to execute // and to read the application base, nothing else PermissionSet restrictedPerms = new PermissionSet(PermissionState.None); restrictedPerms.AddPermission( new SecurityPermission(SecurityPermissionFlag.Execution)); restrictedPerms.AddPermission( new FileIOPermission(FileIOPermissionAccess.Read, appDomainSetup.ApplicationBase); restrictedPerms.AddPermission( new FileIOPermission(FileIOPermissionAccess.pathDiscovery, appDomainSetup.ApplicationBase); // create the sandbox AppDomain sandbox = AppDomain.CreateDomain("Sandbox", null, appDomainSetup, restrictedPerms); // execute UntrustedPlugin in the sandbox // don't crash the application if the sandbox throws an exception IPlugin o = (IPlugin)sandbox.CreateInstanceFromAndUnwrap("Sandboxed.dll", "UntrustedPlugin"); try { o.MethodToDoThings() } catch (Exception e) { Console.WriteLine(e.ToString()); } And the result? Oops. We’ve allowed a class that should be sandboxed to execute code with fully-trusted permissions! How did this happen? Well, the key is the exact meaning of the ApplicationBase property: The application base directory is where the assembly manager begins probing for assemblies. When EvilException is thrown, it propagates from the sandboxed appdomain into the controlling assembly’s appdomain (as it’s marked as Serializable). When the exception is deserialized, the CLR finds and loads the sandboxed dll into the fully-trusted appdomain. Since the controlling appdomain’s ApplicationBase directory contains the sandboxed assembly, the CLR finds and loads the assembly into a full-trust appdomain, and the evil code is executed. So the problem isn’t exactly that the sandboxed appdomain’s ApplicationBase is the same as the controlling appdomain’s, it’s that the sandboxed dll was in such a place that the controlling appdomain could find it as part of the standard assembly resolution mechanism. The sandbox then forced the assembly to load in the controlling appdomain by throwing a serializable exception that propagated outside the sandbox. The easiest fix for this is to keep the sandbox ApplicationBase well away from the ApplicationBase of the controlling appdomain, and don’t allow the sandbox permissions to access the controlling appdomain’s ApplicationBase directory. If you do this, then the sandboxed assembly can’t be accidentally loaded into the fully-trusted appdomain, and the code can’t be executed. If the plugin does try to induce the controlling appdomain to load an assembly it shouldn’t, a SerializationException will be thrown when it tries to load the assembly to deserialize the exception, and no damage will be done. 2. Loading the sandboxed dll into the application appdomain As an extension of the previous point, you shouldn’t directly reference types or methods in the sandboxed dll from your application code. That loads the assembly into the fully-trusted appdomain, and from there code in the assembly could be executed. Instead, pull out methods you want the sandboxed dll to have into an interface or class in a partially-trusted assembly you control, and execute methods via that instead (similar to the example above with the IPlugin interface). If you need to have a look at the assembly before executing it in the sandbox, either examine the assembly using reflection from within the sandbox, or load the assembly into the Reflection-only context in the application’s appdomain. The code in assemblies in the reflection-only context can’t be executed, it can only be reflected upon, thus protecting your appdomain from malicious code. 3. Incorrectly asserting permissions You should only assert permissions when you are absolutely sure they’re safe. For example, this method allows a caller read-access to any file they call this method with, including your documents, any network shares, the C:\Windows directory, etc: [SecuritySafeCritical] public static string GetFileText(string filePath) { new FileIOPermission(FileIOPermissionAccess.Read, filePath).Assert(); return File.ReadAllText(filePath); } Be careful when asserting permissions, and ensure you’re not providing a loophole sandboxed dlls can use to gain access to things they shouldn’t be able to. Conclusion Hopefully, that’s given you an idea of some of the ways it’s possible to get past the .NET security system. As I said before, this post is not exhaustive, and you certainly shouldn’t base any security-critical applications on the contents of this blog post. What this series should help with is understanding the possibilities of the security system, and what all the security attributes and classes mean and what they are used for, if you were to use the security system in the future.

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• Using env variables with RewriteRule and ErrorDocument

  - by misterte

  Hi, I'm having problems with the following while config. my Apache server to Rewrite some urls. SetEnv PATH_TO_DIR /directory RewriteRule ^%{PATH_TO_DIR}/([a-zA-Z0-9_\-]+)/([a-zA-Z0-9_\-\.]+)/?$ /index.php?dir=$1&file=$2 ErrorDocument 404 %{PATH_TO_DIR}/index.php?dir=null&file=error This conf. used to work perfectly fine until I used SetEnv PATH... etc. I need to use this because there are lots of rules, not just those. Can anyone point out my mistake? Apache returns %{PATH_TO_DIR}/index.php?dir=null&file=error when I try anything (www.site.com/foo/bar for instance). Apache returns the ErrorDocument if i just try to fetch the index. I know it's not a problem with the rewrite rules because they work when I remove the PATH_TO_DIR variable and just hard code it. Thanks! A.

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• Solaris 11.2: Functional Deprecation

  - by alanc

  In Solaris 11.1, I updated the system headers to enable use of several attributes on functions, including noreturn and printf format, to give compilers and static analyzers more information about how they are used to give better warnings when building code. In Solaris 11.2, I've gone back in and added one more attribute to a number of functions in the system headers: __attribute__((__deprecated__)). This is used to warn people building software that they’re using function calls we recommend no longer be used. While in many cases the Solaris Binary Compatibility Guarantee means we won't ever remove these functions from the system libraries, we still want to discourage their use. I made passes through both the POSIX and C standards, and some of the Solaris architecture review cases to come up with an initial list which the Solaris architecture review committee accepted to start with. This set is by no means a complete list of Obsolete function interfaces, but should be a reasonable start at functions that are well documented as deprecated and seem useful to warn developers away from. More functions may be flagged in the future as they get deprecated, or if further passes are made through our existing deprecated functions to flag more of them. Header Interface Deprecated by Alternative Documented in <door.h> door_cred(3C) PSARC/2002/188 door_ucred(3C) door_cred(3C) <kvm.h> kvm_read(3KVM), kvm_write(3KVM) PSARC/1995/186 Functions on kvm_kread(3KVM) man page kvm_read(3KVM) <stdio.h> gets(3C) ISO C99 TC3 (Removed in ISO C11), POSIX:2008/XPG7/Unix08 fgets(3C) gets(3C) man page, and just about every gets(3C) reference online from the past 25 years, since the Morris worm proved bad things happen when it’s used. <unistd.h> vfork(2) PSARC/2004/760, POSIX:2001/XPG6/Unix03 (Removed in POSIX:2008/XPG7/Unix08) posix_spawn(3C) vfork(2) man page. <utmp.h> All functions from getutent(3C) man page PSARC/1999/103 utmpx functions from getutentx(3C) man page getutent(3C) man page <varargs.h> varargs.h version of va_list typedef ANSI/ISO C89 standard <stdarg.h> varargs(3EXT) <volmgt.h> All functions PSARC/2005/672 hal(5) API volmgt_check(3VOLMGT), etc. <sys/nvpair.h> nvlist_add_boolean(3NVPAIR), nvlist_lookup_boolean(3NVPAIR) PSARC/2003/587 nvlist_add_boolean_value, nvlist_lookup_boolean_value nvlist_add_boolean(3NVPAIR) & (9F), nvlist_lookup_boolean(3NVPAIR) & (9F). <sys/processor.h> gethomelgroup(3C) PSARC/2003/034 lgrp_home(3LGRP) gethomelgroup(3C) <sys/stat_impl.h> _fxstat, _xstat, _lxstat, _xmknod PSARC/2009/657 stat(2) old functions are undocumented remains of SVR3/COFF compatibility support If the above table is cut off when viewing in the blog, try viewing this standalone copy of the table. To See or Not To See To see these warnings, you will need to be building with either gcc (versions 3.4, 4.5, 4.7, & 4.8 are available in the 11.2 package repo), or with Oracle Solaris Studio 12.4 or later (which like Solaris 11.2, is currently in beta testing). For instance, take this oversimplified (and obviously buggy) implementation of the cat command: #include <stdio.h> int main(int argc, char **argv) { char buf[80]; while (gets(buf) != NULL) puts(buf); return 0; } Compiling it with the Studio 12.4 beta compiler will produce warnings such as: % cc -V cc: Sun C 5.13 SunOS_i386 Beta 2014/03/11 % cc gets_test.c "gets_test.c", line 6: warning: "gets" is deprecated, declared in : "/usr/include/iso/stdio_iso.h", line 221 The exact warning given varies by compilers, and the compilers also have a variety of flags to either raise the warnings to errors, or silence them. Of couse, the exact form of the output is Not An Interface that can be relied on for automated parsing, just shown for example. gets(3C) is actually a special case — as noted above, it is no longer part of the C Standard Library in the C11 standard, so when compiling in C11 mode (i.e. when __STDC_VERSION__ >= 201112L), the <stdio.h> header will not provide a prototype for it, causing the compiler to complain it is unknown: % gcc -std=c11 gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: warning: implicit declaration of function ‘gets’ [-Wimplicit-function-declaration] while (gets(buf) != NULL) ^ The gets(3C) function of course is still in libc, so if you ignore the error or provide your own prototype, you can still build code that calls it, you just have to acknowledge you’re taking on the risk of doing so yourself. Solaris Studio 12.4 Beta % cc gets_test.c "gets_test.c", line 6: warning: "gets" is deprecated, declared in : "/usr/include/iso/stdio_iso.h", line 221 % cc -errwarn=E_DEPRECATED_ATT gets_test.c "gets_test.c", line 6: "gets" is deprecated, declared in : "/usr/include/iso/stdio_iso.h", line 221 cc: acomp failed for gets_test.c This warning is silenced in the 12.4 beta by cc -erroff=E_DEPRECATED_ATT No warning is currently issued by Studio 12.3 & earler releases. gcc 3.4.3 % /usr/sfw/bin/gcc gets_test.c gets_test.c: In function `main': gets_test.c:6: warning: `gets' is deprecated (declared at /usr/include/iso/stdio_iso.h:221) Warning is completely silenced with gcc -Wno-deprecated-declarations gcc 4.7.3 % /usr/gcc/4.7/bin/gcc gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: warning: ‘gets’ is deprecated (declared at /usr/include/iso/stdio_iso.h:221) [-Wdeprecated-declarations] % /usr/gcc/4.7/bin/gcc -Werror=deprecated-declarations gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: error: ‘gets’ is deprecated (declared at /usr/include/iso/stdio_iso.h:221) [-Werror=deprecated-declarations] cc1: some warnings being treated as errors Warning is completely silenced with gcc -Wno-deprecated-declarations gcc 4.8.2 % /usr/bin/gcc gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: warning: ‘gets’ is deprecated (declared at /usr/include/iso/stdio_iso.h:221) [-Wdeprecated-declarations] while (gets(buf) != NULL) ^ % /usr/bin/gcc -Werror=deprecated-declarations gets_test.c gets_test.c: In function ‘main’: gets_test.c:6:5: error: ‘gets’ is deprecated (declared at /usr/include/iso/stdio_iso.h:221) [-Werror=deprecated-declarations] while (gets(buf) != NULL) ^ cc1: some warnings being treated as errors Warning is completely silenced with gcc -Wno-deprecated-declarations

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• How to tackle a boss who thinks everybody in this world is wrong except him?

  - by anon

  I mean seriously, how do you tackle a guy who even changes our variable names (even though they are reasonable) and sends back the code (after review) like 4 times? I know for sure I'm not that bad a developer! So many times, he enforces his ideals, which are not even best practices in the industry! I point out to him whatever link I can find on the internet trying to prove my point, but in the end he uses his authority to shut us out. Sick and tired. Frustrated. Do I have any way out other than quitting the job?

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• VirtualBox appliance for the Oracle Communications Service Delivery Platform (SDP) Products

  - by chlander

  It's been quite awhile since we last blogged. This blog is written by Leif Lourie, a Curriculum Developer for the Oracle Communications Service Delivery Platform (SDP) products. For the last 8 years, Leif has worked as a Curriculum Developer for many of the telecom-oriented products that Oracle offers. He has been working in the telecom industry for about 25 years and has also worked as a software developer, project manager, and solutions architect. He is currently working on courseware for an upcoming release for one of the Service Delivery Platform products. Thanks to Leif not only for this blog, but for making the VM described in the blog available. Cheryl Lander, Oracle Communications InfoDev Senior Director To be able to download, install and test a product within a day is many times very important for people that are doing the primary evaluation of a software product. If it takes longer, it will require a bigger effort, like a proof-of-concept project with many people involved. Of course, if the product is chosen for a more thorough test, it will probably happen anyway, but then maybe with focus on integration instead of product features. We have a long tradition of creating complex software that is easy to install and test and we have often been praised for the ease of getting our products up and running. One key for this has been that there has always been an installer for Windows, as well as for the production environments that usually are Unix and Linux. And, the windows installer has, in most cases, been released for developing and testing purposes. Lately, this has changed. Our products are very seldom released for the Windows platform, at all. And even the Linux versions are almost always released for 64-bit systems. This is creating problems for many of the people that want to try out our products, since few have access to a 64-bit Linux system of the right platform. Most of us are using a laptop with Windows or Mac OS. Some of us are using Linux or Solaris, but probably a non certified distribution for the product you want to test. My job, among other things, is to develop hands-on practices for our products. For me, it is crucial to have access to environments for installing and using our products. For this reason I have been using virtual machines for many years.I have a ready-made base system, with the necessary tools installed for all the products I create hands-on practices for. Whenever I start working on hands-on practices for a new product or a new version, I just copy the base system and start working with a clean slate. This saves me a lot of time! Now, I would like to start saving time for my favorite student: You! If you are using our products and regularly test new versions you might benefit from the virtual machine that is now available on Oracle Technology Network: The Virtual Machine for the Oracle Communications Service Delivery Platform (SDP) Products. This virtual machine contains an installation of the 64-bit version of Oracle Enterprise Linux, version 6. It also has Oracle Database Express Edition (XE), Oracle Java and Oracle Enterprise Pack for Eclipse installed. By using Oracle VM VirtualBox you may use Windows, OS X, Linux or Solaris on your laptop. VirtualBox can be installed on top of any of these platforms and give you the ability to run virtual machines in your laptop. After downloading and starting the virtual machine you will also need to download the installation files for the product you want to test; for example Oracle Communications Services Gatekeeper or Oracle Communications Online Mediation Controller. In some cases there are lessons and practices available for the products. The freely available courses are listed in Oracle Learning Library as a Collection of Oracle Communications Service Delivery Platform Courses. As time goes by, we will make this list collection bigger. Also, the goal is to update the virtual machine about one to two times per year. So you will always be able to get a well maintained virtual machine for the Service Delivery Platform products from us. We Value Your Feedback If you would like to suggest improvements or report issues on any of the product documentation, curriculum, or training produced by the Oracle Communications Information Development team, you can use these channels: Email [email protected]. Post a comment on this blog. Thanks for reading!

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• Training a 'replacement', how to enforce standards?

  - by Mohgeroth

  Not sure that this is the right stack exchange site to ask this of, but here goes... Scope I work for a small company that employs a few hundred people. The development team for the company is small and works out of visual foxpro. A specific department in the company hired me in as a 'lone gunman' to fix and enhance a pre-existing invoicing system. I've successfully taken an Access application that suffered from a lot of risks and limitations and converted it into a C# application driven off of a SQL server backend. I have recently obtained my undergraduate and am no expert by any means. To help make up for that I've felt that earning microsoft certifications will force me to understand more about .net and how it functions. So, after giving my notice with 9 months in advance, 3 months ago a replacement finally showed up. Their role is to learn what I have been designing to an attempt to support the applications designed in C#. The Replacement Fresh out of college with no real-world work experience, the first instinct for anything involving data was and still is listboxes... any time data is mentioned the list box is the control of choice for the replacement. This has gotten to the point, no matter how many times I discuss other controls, where I've seen 5 listboxes on a single form. Classroom experience was almost all C++ console development. So, an example of where I have concern is in a winforms application: Users need to key Reasons into a table to select from later. Given that I know that a strongly typed data set exists, I can just drag the data source from the toolbox and it would create all of this for me. I realize this is a simple example but using databinding is the key. For the past few months now we have been talking about the strongly typed dataset, how to use it and where it interacts with other controls. Data sets, how they work in relation to binding sources, adapters and data grid views. After handing this project off I expected questions about how to implement these since for me this is the way to do it. What happened next simply floors me: An instance of an adapter from the strongly typed dataset was created in the activate event of the form, a table was created and filled with data. Then, a loop was made to manually add rows to a listbox from this table. Finally, a variable was kept to do lookups to figure out what ID the record was for updates if required. How do they modify records you ask? That was my first question too. You won't believe how simple it is, all you do it double click and they type into a pop-up prompt the new value to change it to. As a data entry operator, all the modal popups would drive me absolutely insane. The final solution exceeds 100 lines of code that must be maintained. So my concern is that none of this is sinking in... the department is only allowed 20 hours a week of their time. Up until last week, we've only been given 4-5 hours a week if I'm lucky. The past week or so, I've been lucky to get 10. Question WHAT DO I DO?! I have 4 weeks left until I leave and they fully 'support' this application. I love this job and the opportunity it has given me but it's time for me to spread my wings and find something new. I am in no way, shape or form convinced that they are ready to take over. I do feel that the replacement has the technical ability to 'figure it out' but instead of learning they just write code to do all of this stuff manually. If the replacement wants to code differently in the end, as long as it works I'm fine with that as horrifiying at it looks. However to support what I have designed they MUST to understand how it works and how I have used controls and the framework to make 'magic' happen. This project has about 40 forms, a database with over 30 some odd tables, triggers and stored procedures. It relates labor to invoices to contracts to projections... it's not as simple as it was three years ago when I began this project and the department is now in a position where they cannot survive without it. How in the world can I accomplish any of the following?: Enforce standards or understanding in constent design when the department manager keeps telling them they can do it however they want to Find a way to engage the replacement in active learning of the framework and system design that support must be given for Gracefully inform sr. management that 5-9 hours a week is simply not enough time to learn about the department, pre-existing processes, applications that need to be supported AND determine where potential enhancements to the system go... Yes I know this is a wall of text, thanks for reading through me but I simply don't know what I should be doing. For me, this job is a monster of a reference and things would look extremely bad if I left and things fell apart. How do I handle this?

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• Oracle Sequences

  - by jkrebsbach

  Reminder to myself - SQL Server has nice index columns directly tied to their tables. Oracle has sequences that are islands to themselves. select seq_name.currval from dual; select seq_name.nextval from dual; currval - return current number at top of sequence nextval - increment sequence by 1, return new number   therefore - to create functionality in oracle similar to an index column - OPTION A) - Create insert trigger: CREATE OR REPLACE TRIGGER dept_bir BEFORE INSERT ON departments FOR EACH ROW WHEN (new.id IS NULL) BEGIN SELECT dept_seq.NEXTVAL INTO :new.id FROM dual; END; This will handle creating a unique identity, but will not necessarily inform process flow of identity without additional logic. OPTION B) - Select indentity into temp variable, insert whole item into tab **** When attemptint to query currval, the below error was being thrown - SELECT seq_name.currval from dual; ERROR : TABLE OR VIEW DOES NOT EXIST *** Although Oracle sys tables may have access to the sequences, that isn't to say the Oracle user may have access to those sequences - verify permissions when the system can't see object that are being reported in the object explorer.

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• How do I generate a level randomly?

  - by Charlton Santana

  I am currently hard coding 10 different instances like the code below, but but I'd like to create many more. Instead of having the same layout for the new level, I was wondering if there is anyway to generate a random X value for each block (this will be how far into the level it is). A level 100,000 pixels wide would be good enough but if anyone knows a system to make the level go on and on, I'd like to know that too. This is basically how I define a block now (with irrelevant code removed): block = new Block(R.drawable.block, 400, platformheight); block2 = new Block(R.drawable.block, 600, platformheight); block3 = new Block(R.drawable.block, 750, platformheight); The 400 is the X position, which I'd like to place randomly through the level, the platformheight variable defines the Y position which I don't want to change.

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• Can't see my partitions after grub recovery

  - by dimbo

  I stupidly inserted the windows CD into my dual boot Ubuntu 11.10 / windows xp system. I just wanted to see if I could install windows on my external usb HD, but didn't actually go ahead with the install. It seems like the windows CD messed up my MBR and I had to use boot-repair and the ubuntu 11.10 live CD to gain access to ubuntu again. It seems to boot up a little differently (slower) but works. However, I now cant see any of my partitions in nautilus (there are 3). When I open gparted, it just shows my whole hard drive as unallocated (I know it has a windows partition that works and my ubuntu partition that I am using now). If I insert a usb pen, it is also not visible in nautilus but in gparted shows up as a FAT32 partition (which is correct although I cannot access it). sudo fdisk -l gives the following : demian@dimbo-TP:~$ sudo fdisk -l [sudo] password for demian: omitting empty partition (5) Disk /dev/sda: 320.1 GB, 320072933376 bytes 240 heads, 63 sectors/track, 41345 cylinders, total 625142448 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x877b877b Device Boot Start End Blocks Id System /dev/sda1 * 63 63842309 31921123+ 7 HPFS/NTFS/exFAT /dev/sda2 63844350 133484084 34819867+ 5 Extended /dev/sda3 127636488 133484084 2923798+ 82 Linux swap / Solaris /dev/sda4 133484085 625137344 245826630 83 Linux /dev/sda5 63844352 123445247 29800448 83 Linux /dev/sda6 123447296 127635455 2094080 82 Linux swap / Solaris Disk /dev/sdb: 8100 MB, 8100249600 bytes 12 heads, 40 sectors/track, 32960 cylinders, total 15820800 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xc3072e18 Device Boot Start End Blocks Id System /dev/sdb1 * 5992 15820799 7907404 c W95 FAT32 (LBA) Here is my grub.conf file. Like I said before, I had to use the 'boot-repair' utility with the live cd to get grub working again. I think that this utility maybe created a new grub for me because the startup is definitely not the same. The screen goes blank for a while, and then the ubuntu loading dots come up for a brief moment (instead of during the whole startup process) before the dektop is displayed. Anyway : # DO NOT EDIT THIS FILE # # It is automatically generated by grub-mkconfig using templates # from /etc/grub.d and settings from /etc/default/grub # ### BEGIN /etc/grub.d/00_header ### if [ -s $prefix/grubenv ]; then set have_grubenv=true load_env fi set default="0" if [ "${prev_saved_entry}" ]; then set saved_entry="${prev_saved_entry}" save_env saved_entry set prev_saved_entry= save_env prev_saved_entry set boot_once=true fi function savedefault { if [ -z "${boot_once}" ]; then saved_entry="${chosen}" save_env saved_entry fi } function recordfail { set recordfail=1 if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi } function load_video { insmod vbe insmod vga insmod video_bochs insmod video_cirrus } insmod part_msdos insmod ext2 set root='(hd0,msdos6)' search --no-floppy --fs-uuid --set=root 5349ff67-b7b7-489f-a881-ae49c1dcd84a if loadfont /usr/share/grub/unicode.pf2 ; then set gfxmode=auto load_video insmod gfxterm insmod part_msdos insmod ext2 set root='(hd0,msdos6)' search --no-floppy --fs-uuid --set=root 5349ff67-b7b7-489f-a881-ae49c1dcd84a set locale_dir=($root)/boot/grub/locale set lang=en_US insmod gettext fi terminal_output gfxterm if [ "${recordfail}" = 1 ]; then set timeout=10 else set timeout=10 fi ### END /etc/grub.d/00_header ### ### BEGIN /etc/grub.d/05_debian_theme ### set menu_color_normal=white/black set menu_color_highlight=black/light-gray if background_color 44,0,30; then clear fi ### END /etc/grub.d/05_debian_theme ### ### BEGIN /etc/grub.d/10_linux ### if [ ${recordfail} != 1 ]; then if [ -e ${prefix}/gfxblacklist.txt ]; then if hwmatch ${prefix}/gfxblacklist.txt 3; then if [ ${match} = 0 ]; then set linux_gfx_mode=keep else set linux_gfx_mode=text fi else set linux_gfx_mode=text fi else set linux_gfx_mode=keep fi else set linux_gfx_mode=text fi export linux_gfx_mode if [ "$linux_gfx_mode" != "text" ]; then load_video; fi menuentry 'Ubuntu, with Linux 3.0.0-12-generic' --class ubuntu --class gnu-linux --class gnu --class os { recordfail set gfxpayload=$linux_gfx_mode insmod gzio insmod part_msdos insmod ext2 set root='(hd0,msdos6)' search --no-floppy --fs-uuid --set=root 5349ff67-b7b7-489f-a881-ae49c1dcd84a linux /boot/vmlinuz-3.0.0-12-generic root=UUID=5349ff67-b7b7-489f-a881-ae49c1dcd84a ro quiet splash vt.handoff=7 initrd /boot/initrd.img-3.0.0-12-generic } menuentry 'Ubuntu, with Linux 3.0.0-12-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os { recordfail insmod gzio insmod part_msdos insmod ext2 set root='(hd0,msdos6)' search --no-floppy --fs-uuid --set=root 5349ff67-b7b7-489f-a881-ae49c1dcd84a echo 'Loading Linux 3.0.0-12-generic ...' linux /boot/vmlinuz-3.0.0-12-generic root=UUID=5349ff67-b7b7-489f-a881-ae49c1dcd84a ro recovery nomodeset echo 'Loading initial ramdisk ...' initrd /boot/initrd.img-3.0.0-12-generic } ### END /etc/grub.d/10_linux ### ### BEGIN /etc/grub.d/20_linux_xen ### ### END /etc/grub.d/20_linux_xen ### ### BEGIN /etc/grub.d/20_memtest86+ ### menuentry "Memory test (memtest86+)" { insmod part_msdos insmod ext2 set root='(hd0,msdos6)' search --no-floppy --fs-uuid --set=root 5349ff67-b7b7-489f-a881-ae49c1dcd84a linux16 /boot/memtest86+.bin } menuentry "Memory test (memtest86+, serial console 115200)" { insmod part_msdos insmod ext2 set root='(hd0,msdos6)' search --no-floppy --fs-uuid --set=root 5349ff67-b7b7-489f-a881-ae49c1dcd84a linux16 /boot/memtest86+.bin console=ttyS0,115200n8 } ### END /etc/grub.d/20_memtest86+ ### ### BEGIN /etc/grub.d/30_os-prober ### menuentry "Microsoft Windows XP Professional (on /dev/sda1)" --class windows --class os { insmod part_msdos insmod ntfs set root='(hd0,msdos1)' search --no-floppy --fs-uuid --set=root 72A89361A89322A1 drivemap -s (hd0) ${root} chainloader +1 } ### END /etc/grub.d/30_os-prober ### ### BEGIN /etc/grub.d/40_custom ### # This file provides an easy way to add custom menu entries. Simply type the # menu entries you want to add after this comment. Be careful not to change # the 'exec tail' line above. ### END /etc/grub.d/40_custom ### ### BEGIN /etc/grub.d/41_custom ### if [ -f $prefix/custom.cfg ]; then source $prefix/custom.cfg; fi ### END /etc/grub.d/41_custom ### How can I get things back to normal. Thanks, Demian.

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• Initialized variables vs named constants

  - by Mike

  I'm working on a fundamental programming class in college and our textbook is "programming logic and design" by joyce farrell(spelling?) Anyhow, I'm struggling conceptually when it comes to initialized variables and named constants. Our class is focusing on pseudo-code for the time being and not one particular language so let me illustrate what I'm talking about. Let's say I am declaring a variable named "myVar" and the data type is numeric: num myVar now I want to initialize it (I don't understand this concept) starting with the number 5 num myVar = 5 how is that any different than creating a named constant?

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• Finding the html tag value with Python [on hold]

  - by MrWho

  Consider a html page, which contains a line like below: file: 'http://google.com/video.mp4' I want to search for google.com/video.mp4 in that file and save it in a variable.I want to code it with python. Shortly, I want to elicit a link from a html page, so I need to get the link by using regular expressions or the other techniques in which I'm asking about. PS: What should I exactly try to clarify?it's really annoying that the administrators don't even say what is exactly unclear about the question, they've just learned to close or on hold the topics!

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• New T-SQL Functionality in SQL Server 2008

  - by ejohnson2010

  In my most recent posts I have looked at a few of the new features offered in T-SQL in SQL Server 2008. In this post, I want to take a closer look at some of the smaller additions, but additions that are likely to pack a big punch in terms of efficiency. First let’s talk a little about compound operators. This is a concept that has been around in programming languages for a long time, but has just now found its way into T-SQL. For example, the += operator will add the values to the current variable...(read more)

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• Level and Player objects - which should contain which?

  - by Thane Brimhall

  I've been working on a several simple games, and I've always come to a decision point where I have to choose whether to have the Level object as an attribute of the Player class or the Player as an attribute of the Level class. I can see arguments for both: The Level should contain the player because it also contains every other entity. In fact it just makes sense this way: "John is in the room." It makes it a bit more difficult to move the player to a new level, however, because then each level has to pass its player object to an upcoming level. On the other hand, it makes programming sense to me to leave the player as the top-level object that is persistent between levels, and the environment changes because the player decides to change his level and location. It becomes very easy to change levels, because all I have to do is replace the level variable on the player. What's the most common practice here? Or better yet, is there a "right" way to architecture this relationship?

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• Is it possible to run the GNOME user manager from XFCE4?

  - by Chris Moore

  If I run 'gnome-control-center' and click on the 'User Accounts' icon, the gnome-control-center crashes. I built it from source to see what's going on, and it turns out it's doing a if (strcmp(getenv("XDG_CURRENT_DESKTOP"), "GNOME")) in panels/user-accounts/um-password-dialog.c, line 690. I don't have an environment variable "XDG_CURRENT_DESKTOP", so the getenv is returning NULL, and the strcmp is segfaulting Where is XDG_CURRENT_DESKTOP meant to be defined? And shouldn't gnome-control-center check the pointer returned by getenv before passing it to strcmp? Does xfce4 have its own 'User Accounts' tool for creating new users?

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• Creating a curved mesh on inside of sphere based on texture image coordinates

  - by user5025

  In Blender, I have created a sphere with a panoramic texture on the inside. I have also manually created a plane mesh (curved to match the size of the sphere) that sits on the inside wall where I can draw a different texture. This is great, but I really want to reduce the manual labor, and do some of this work in a script -- like having a variable for the panoramic image, and coordinates of the area in the photograph that I want to replace with a new mesh. The hardest part of doing this is going to be creating a curved mesh in code that can sit on the inside wall of a sphere. Can anyone point me in the right direction?

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• How to decide whether to implement an operation as Entity operation vs Service operation in Domain Driven Design?

  - by Louis Rhys

  I am reading Evans's Domain Driven Design. The book says that there are entity and there are services. If I were to implement an operation, how to decide whether I should add it as a method on an entity or do it in a service class? e.g. myEntity.DoStuff() or myService.DoStuffOn(myEntity)? Does it depend on whether other entities are involved? If it involves other entities, implement as service operation? But entities can have associations and can traverse it from there too right? Does it depend on stateless or not? But service can also access entities' variable, right? Like in do stuff myService.DoStuffOn, it can have code like if(myEntity.IsX) doSomething(); Which means that it will depend on the state? Or does it depend on complexity? How do you define complex operations?

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• Is it good practice to use functions just to centralize common code?

  - by EpsilonVector

  I run across this problem a lot. For example, I currently write a read function and a write function, and they both check if buf is a NULL pointer and that the mode variable is within certain boundaries. This is code duplication. This can be solved by moving it into its own function. But should I? This will be a pretty anemic function (doesn't do much), rather localized (so not general purpose), and doesn't stand well on its own (can't figure out what you need it for unless you see where it is used). Another option is to use a macro, but I want to talk about functions in this post. So, should you use a function for something like this? What are the pros and cons?

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• VS2010 crashes when opening a vsp generated using VS 2012

  - by Tarun Arora

  I recently profiled some web applications using Visual Studio 2012, a vsp (Visual Studio Profile) file was generated as a result of the profiling session. I could successfully open the vsp file in Visual Studio 2012 as expected but when I tried to open the vsp file in Visual Studio 2010 the VS2010 IDE crashed. As a responsible citizen I raised bug # 762202 on Microsoft Connect site using the Microsoft Visual Studio 2012 Feedback Client. Note – In case you didn’t already know, VSP generated in Visual Studio 2012 is not backward compatible. Please refer below for the steps to reproduce the issue and the resolution of the connect bug. 1. Behaviour and Steps to Reproduce the Issue Description I have generated a vsp file by using the Visual Studio 2012 Standalone profiler. When I try and open the vsp file in Visual Studio 2010 the IDE crashes. I understand that a vsp generated by using VS 2012 cannot be opened in VS 2010, but the IDE crashing is not the behaviour I would expect to see. Steps to Reproduce the Issue 1. Pick up the Stand lone profiler from the VS 2012 installation media. The folder has both x 64 and x86 installer, since the machine I am using is x64 bit. I have installed the x64 version of the standalone profiler. 2. I have configured the system path by setting the 'environment variable' path to where the profiler is installed. In my case this is, C:\Program Files (x86)\Microsoft Visual Studio 11.0\Team Tools\Performance Tools 3. Created a new environment variable _NT_SYMBOL_PATH and set its value to CACHE*C:\SYMBOLSCACHE;SRV*C:\SYMBOLSCACHE*HTTP://MSDL.MICROSOFT.COM/DOWNLOAD/SYMBOLS;\\FOO\BUILD1234 4. Open up CMD as an administrator and run 'VSPerfASPNETCmd /tip http://localhost:56180/ /o:C:\Temp\SampleEISK.vsp' 5. This generates the following message on the cmd       Microsoft (R) VSPerf ASP.NET Command, Version 11.0.0.0     Copyright (C) Microsoft Corporation. All rights reserved.     Configuring and attaching to ASP.NET process. Please wait.     Setting up profiling environment.     Starting monitor.     Launching ASP.NET service.     Attaching Monitor to process.     Launching Internet Explorer.     The profiler is attached to ASP.net. Please run your application scenario now.     Press Enter to stop data collection...   6. I perform certain actions and then I come back to the cmd and hit enter to shut down the profiling. Once I do this, the following message is written to the cmd, Press Enter to stop data collection... Profiling now shut down. Report file "C:\Temp\SampleEISK.vsp" was generated. Running VsPerfReport, packing symbols into the .VSP. Shutting down profiling and restarting ASP.NET. Please wait. Restarting w3wp.exe.   7. I look in the C:\Temp folder and I can see the SampleEISK.vsp file generated. I can successfully open this file in Visual Studio 2012. 8. When I am trying to open the vsp file in VS 2010 the VS 2010 IDE crashes. Kaboooom! What I would expect to happen I expect to receive a message "VS 2010 does not support the vsp file generated by VS 2012". What actually happened The VS 2010 IDE crashed 2. Resolution This is a valid bug! However, there isn’t much value in releasing a hotfix for this issue. Refer below to the resolution provided by the Visual Studio Profiler Team.  Thank you for taking the time to report this issue. We completely agree that Visual Studio 2010 should not crash. However in this particular case this is not a bug we are going to retroactively release a fix to 2010 for at this point. Given that a fix would not unblock the scenario of opening a 2012 created file on Visual Studio 2010, and there is not an active update channel for Visual Studio 2010 other than manually locating and installing hot fixes, we will not be fixing this particular issue. Best Regards, Visual Studio Profiler Team   Though it would be great to improve the behaviour however, this is not a defect that would stop you from progressing in any way. It’s important to note however that VSP files generated by Visual Studio 2012 are not backward compatible so you should refrain from opening these files in Visual Studio 2010.

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• MacBook Pro (5) touchpad stops working after upgrading from Ubuntu 10.10 to Ubuntu 11.04

  - by Rob

  After upgrading from Ubuntu 10.10 to Ubuntu 11.04, my MacBook Pro's touchpad stopped working. It works fine on the login screen, but after logging in it stops working. (Answering my own question, in the hope that it saves someone else a bit of head scratching. I'm a new user, so couldn't answer in a separate post for the next few hours). After the upgrade, your Gnome desktop configuration may have gone awry. There are a few settings which enable or disable the touchpad in certain contexts which may need tweaking to get the touchpad working again. Here's how I got mine working again: Hit Alt-F2, and run 'gconf-editor' Navigate to desktop-gnome-peripherals Ensure that peripherals-touchpad:touchpad is enabled. Ensure that peripherals-bcm5974:disable_while_other_device_exists is disabled. 'bcm5974' is probably specific to my MacBook Pro's hardware, so you may need to search around for variable disable_while_other_device_exists under the entries listed under peripherals. HTH

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• Using Stored Procedures in SSIS

  - by dataintegration

  The SSIS Data Flow components: the source task and the destination task are the easiest way to transfer data in SSIS. Some data transactions do not fit this model, they are procedural tasks modeled as stored procedures. In this article we show how you can call stored procedures available in RSSBus ADO.NET Providers from SSIS. In this article we will use the CreateJob and the CreateBatch stored procedures available in RSSBus ADO.NET Provider for Salesforce, but the same steps can be used to call a stored procedure in any of our data providers. Step 1: Open Visual Studio and create a new Integration Services Project. Step 2: Add a new Data Flow Task to the Control Flow window. Step 3: Open the Data Flow Task and add a Script Component to the data flow pane. A dialog box will pop-up allowing you to select the Script Component Type: pick the source type as we will be outputting columns from our stored procedure. Step 4: Double click the Script Component to open the editor. Step 5: In the "Inputs and Outputs" settings, enter all the columns you want to output to the data flow. Ensure the correct data type has been set for each output. You can check the data type by selecting the output and then changing the "DataType" property from the property editor. In our example, we'll add the column JobID of type String. Step 6: Select the "Script" option in the left-hand pane and click the "Edit Script" button. This will open a new Visual Studio window with some boiler plate code in it. Step 7: In the CreateOutputRows() function you can add code that executes the stored procedures included with the Salesforce Component. In this example we will be using the CreateJob and CreateBatch stored procedures. You can find a list of the available stored procedures along with their inputs and outputs in the product help. //Configure the connection string to your credentials String connectionString = "Offline=False;user=myusername;password=mypassword;access token=mytoken;"; using (SalesforceConnection conn = new SalesforceConnection(connectionString)) { //Create the command to call the stored procedure CreateJob SalesforceCommand cmd = new SalesforceCommand("CreateJob", conn); cmd.CommandType = CommandType.StoredProcedure; cmd.Parameters.Add(new SalesforceParameter("ObjectName", "Contact")); cmd.Parameters.Add(new SalesforceParameter("Action", "insert")); //Execute CreateJob //CreateBatch requires JobID as input so we store this value for later SalesforceDataReader rdr = cmd.ExecuteReader(); String JobID = ""; while (rdr.Read()) { JobID = (String)rdr["JobID"]; } //Create the command for CreateBatch, for this example we are adding two new rows SalesforceCommand batCmd = new SalesforceCommand("CreateBatch", conn); batCmd.CommandType = CommandType.StoredProcedure; batCmd.Parameters.Add(new SalesforceParameter("JobID", JobID)); batCmd.Parameters.Add(new SalesforceParameter("Aggregate", "<Contact><Row><FirstName>Bill</FirstName>" + "<LastName>White</LastName></Row><Row><FirstName>Bob</FirstName><LastName>Black</LastName></Row></Contact>")); //Execute CreateBatch SalesforceDataReader batRdr = batCmd.ExecuteReader(); } Step 7b: If you had specified output columns earlier, you can now add data into them using the UserComponent Output0Buffer. For example, we had set an output column called JobID of type String so now we can set a value for it. We will modify the DataReader that contains the output of CreateJob like so:. while (rdr.Read()) { Output0Buffer.AddRow(); JobID = (String)rdr["JobID"]; Output0Buffer.JobID = JobID; } Step 8: Note: You will need to modify the connection string to include your credentials. Also ensure that the System.Data.RSSBus.Salesforce assembly is referenced and include the following using statements to the top of the class: using System.Data; using System.Data.RSSBus.Salesforce; Step 9: Once you are done editing your script, save it, and close the window. Click OK in the Script Transformation window to go back to the main pane. Step 10: If had any outputs from the Script Component you can use them in your data flow. For example we will use a Flat File Destination. Configure the Flat File Destination to output the results to a file, and you should see the JobId in the file. Step 11: Your project should be ready to run.

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• Getting My Head Around Immutability

  - by Michael Mangold

  I'm new to object-oriented programming, and one concept that has been taking me a while to grasp is immutability. I think the light bulb went off last night but I want to verify: When I come across statements that an immutable object cannot be changed, I'm puzzled because I can, for instance, do the following: NSString *myName = @"Bob"; myName = @"Mike"; There, I just changed myName, of immutable type NSString. My problem is that the word, "object" can refer to the physical object in memory, or the abstraction, "myName." The former definition applies to the concept of immutability. As for the variable, a more clear (to me) definition of immutability is that the value of an immutable object can only be changed by also changing its location in memory, i.e. its reference (also known as its pointer). Is this correct, or am I still lost in the woods?

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• Namespaces are obsolete

  - by Bertrand Le Roy

  To those of us who have been around for a while, namespaces have been part of the landscape. One could even say that they have been defining the large-scale features of the landscape in question. However, something happened fairly recently that I think makes this venerable structure obsolete. Before I explain this development and why it’s a superior concept to namespaces, let me recapitulate what namespaces are and why they’ve been so good to us over the years… Namespaces are used for a few different things: Scope: a namespace delimits the portion of code where a name (for a class, sub-namespace, etc.) has the specified meaning. Namespaces are usually the highest-level scoping structures in a software package. Collision prevention: name collisions are a universal problem. Some systems, such as jQuery, wave it away, but the problem remains. Namespaces provide a reasonable approach to global uniqueness (and in some implementations such as XML, enforce it). In .NET, there are ways to relocate a namespace to avoid those rare collision cases. Hierarchy: programmers like neat little boxes, and especially boxes within boxes within boxes. For some reason. Regular human beings on the other hand, tend to think linearly, which is why the Windows explorer for example has tried in a few different ways to flatten the file system hierarchy for the user. 1 is clearly useful because we need to protect our code from bleeding effects from the rest of the application (and vice versa). A language with only global constructs may be what some of us started programming on, but it’s not desirable in any way today. 2 may not be always reasonably worth the trouble (jQuery is doing fine with its global plug-in namespace), but we still need it in many cases. One should note however that globally unique names are not the only possible implementation. In fact, they are a rather extreme solution. What we really care about is collision prevention within our application. What happens outside is irrelevant. 3 is, more than anything, an aesthetical choice. A common convention has been to encode the whole pedigree of the code into the namespace. Come to think about it, we never think we need to import “Microsoft.SqlServer.Management.Smo.Agent” and that would be very hard to remember. What we want to do is bring nHibernate into our app. And this is precisely what you’ll do with modern package managers and module loaders. I want to take the specific example of RequireJS, which is commonly used with Node. Here is how you import a module with RequireJS: var http = require("http"); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This is of course importing a HTTP stack module into the code. There is no noise here. Let’s break this down. Scope (1) is provided by the one scoping mechanism in JavaScript: the closure surrounding the module’s code. Whatever scoping mechanism is provided by the language would be fine here. Collision prevention (2) is very elegantly handled. Whereas relocating is an afterthought, and an exceptional measure with namespaces, it is here on the frontline. You always relocate, using an extremely familiar pattern: variable assignment. We are very much used to managing our local variable names and any possible collision will get solved very easily by picking a different name. Wait a minute, I hear some of you say. This is only taking care of collisions on the client-side, on the left of that assignment. What if I have two libraries with the name “http”? Well, You can better qualify the path to the module, which is what the require parameter really is. As for hierarchical organization, you don’t really want that, do you? RequireJS’ module pattern does elegantly cover the bases that namespaces used to cover, but it also promotes additional good practices. First, it promotes usage of self-contained, single responsibility units of code through the closure-based, stricter scoping mechanism. Namespaces are somewhat more porous, as using/import statements can be used bi-directionally, which leads us to my second point… Sane dependency graphs are easier to achieve and sustain with such a structure. With namespaces, it is easy to construct dependency cycles (that’s bad, mmkay?). With this pattern, the equivalent would be to build mega-components, which are an easier problem to spot than a decay into inter-dependent namespaces, for which you need specialized tools. I really like this pattern very much, and I would like to see more environments implement it. One could argue that dependency injection has some commonalities with this for example. What do you think? This is the half-baked result of some morning shower reflections, and I’d love to read your thoughts about it. What am I missing?

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• What are the basic skills a beginner JavaScript programmer should have?

  - by Sanford

  In NYC, we are working on creating a collaborative community programming environment and trying to segment out software engineers into differing buckets. At present, we are trying to define: Beginners Intermediates Advanced Experts (and/or Masters) Similar to an apprenticeship, you would need to demonstrate specific skills to achieve different levels. Right now, we have identified beginner programming skills as: Object - method, attributes, inheritance Variable - math, string, array, boolean - all are objects Basic arithmetic functions - precedence of functions String manipulation Looping - flow control Conditionals - boolean algebra This is a first attempt, and it is a challenge since we know the natural tension between programming and software engineering. How would you create such a skills-based ranking for JavaScript in this manner? For example, what would be the beginner JavaScript skills that you would need to have to advance to the intermediate training? And so on.

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