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• Acer Aspire One 725 - missing graphic card driver?

  - by Melon

  Recently I bought an Acer Aspire One 725 Netbook and installed Ubuntu 12.10 on it. I bought it, because it can run HD movies and has Full HD on external VGA port. However, movies from youtube have a really slow framerate. If you open three tabs in Opera (for example g-mail, youtube and askubuntu) it gets really laggy. My suspicion is that the driver for graphic card is missing. When I check the System->Details->Graphics the driver is unknown. After running lspci | grep VGA I get this output: 00:01.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI Device 980a From what I see, I have a AMD C70 processor integrated with (or something similar) AMD Radeon HD 6290. Has anyone had the same problem? Do you know which drivers need to be installed for the graphics to work properly? On official Acer page there are only drivers for Win7 and Win8... Update: I have tried installing fglrx but I get the following error (either I don't have libraries or someone didn't make a clean build before release ;) /lib/modules/fglrx/build_mod/2.6.x/firegl_public.c: In function ‘KCL_MEM_AllocLinearAddrInterval’: /lib/modules/fglrx/build_mod/2.6.x/firegl_public.c:2124:5: error: implicit declaration of function ‘do_mmap’ [-Werror=implicit-function-declaration] /lib/modules/fglrx/build_mod/2.6.x/firegl_public.c:2124:13: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] /lib/modules/fglrx/build_mod/2.6.x/firegl_public.c: In function ‘kasInitExecutionLevels’: /lib/modules/fglrx/build_mod/2.6.x/firegl_public.c:4159:5: error: ‘cpu_possible_map’ undeclared (first use in this function) /lib/modules/fglrx/build_mod/2.6.x/firegl_public.c:4159:5: note: each undeclared identifier is reported only once for each function it appears in /lib/modules/fglrx/build_mod/2.6.x/firegl_public.c:4159:5: warning: left-hand operand of comma expression has no effect [-Wunused-value] Update 2: After fixing the erros in compilation, ubuntu acts bizarre and unstable (no left icon panel, no upper panel, cannot run any programs, I only see desktop)

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• Is there a modified LGPL license that allows static linking?

  - by Petr Pudlák

  úLGPL requires that it if a program uses LGPL-ed library, users must be able to re-link the program with a different version of the library: ... d) Do one of the following: 0) Convey the Minimal Corresponding Source under the terms of this License, and the Corresponding Application Code in a form suitable for, and under terms that permit, the user to recombine or relink the Application with a modified version of the Linked Version to produce a modified Combined Work, in the manner specified by section 6 of the GNU GPL for conveying Corresponding Source. 1) Use a suitable shared library mechanism for linking with the Library. A suitable mechanism is one that (a) uses at run time a copy of the Library already present on the user's computer system, and (b) will operate properly with a modified version of the Library that is interface-compatible with the Linked Version. ... However in some cases, this can pose considerable difficulties. In particular, Haskell programs are almost always statically compiled. Moreover, the compiler does cross-module optimizations so it's very hard to satisfy this condition. (See this link at Haskell Wiki.) Therefore, I'm looking for a standard LGPL-like license that wouldn't require the possibility of re-linking. Some projects use their own modification of LGPL, for example wxWidgets. But I'd rather use some standard license that is somewhat more official, perhaps checked by some law experts, and (L)GPL compatible. Is there some like that? (Also I'd be interested to know if are there some unforeseen consequences of such a modification of LGPL.)

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• How to manually set color of Unity Panel?

  - by JamesTheAwesomeDude

  I was just wondering if there's a way to set the color of the Unity panel manually, as opposed to having it derived from smooshing all the colors of the wallpaper together. (the launcher on the left side of the screen that comes default in Ubuntu is the Unity Panel, right? If not, please correct me on my terminology.) The reason I want this is because I have this cool wallpaper I found on DeviantArt, and I used GIMP to make Dawn, Dusk, and Midnight versions of it. Then, I set them with a transition effect, so that the lighting changes over the course of the day. Unfortunately, the Unity Panel turns a sickly sewer green at night (it could also be said to look like radioactive barf.) Either way, I don't like my launcher thingy looking like that. I'd prefer to stay away from programs that let you customise the Unity Panel (I'm fine with using sudo nano to edit system config files,) but I would if it were the only option. Here are some screenshots, one with a grey-themed wallpaper, one with lots of red, and the hill at night, (the one that makes the unity panel look like radioactive barf.): http://imgur.com/a/0Gqcd

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• ORA-4031 Troubleshooting

  - by [email protected]

    QUICKLINK: Note 396940.1 Troubleshooting and Diagnosing ORA-4031 Error Note 1087773.1 : ORA-4031 Diagnostics Tools [Video]   Have you observed an ORA-04031 error reported in your alert log? An ORA-4031 error is raised when memory is unavailable for use or reuse in the System Global Area (SGA).  The error message will indicate the memory pool getting errors and high level information about what kind of allocation failed and how much memory was unavailable.  The challenge with ORA-4031 analysis is that the error and associated trace is for a "victim" of the problem.   The failing code ran into the memory limitation, but in almost all cases it was not part of the root problem.    Looking for the best way to diagnose? When an ORA-4031 error occurs, a trace file is raised and noted in the alert log if the process experiencing the error is a background process.   User processes may experience errors without reports in the alert log or traces generated.   The V$SHARED_POOL_RESERVED view will show reports of misses for memory over the life of the database. Diagnostics scripts are available in Note 430473.1 to help in analysis of the problem.  There is also a training video on using and interpreting the script data Note 1087773.1. 11g DiagnosabilityStarting with Oracle Database 11g Release 1, the Diagnosability infrastructure was introduced which places traces and core files into a location controlled by the DIAGNOSTIC_DEST initialization parameter when an incident, such as an ORA-4031 occurs. For earlier versions, the trace file will be written to either USER_DUMP_DEST (if the error was caught in a user process) or BACKGROUND_DUMP_DEST (if the error was caught in a background process like PMON or SMON). The trace file contains vital information about what led to the error condition.  Note 443529.1 11g Quick Steps to Package and Send Critical Error Diagnostic Information to Support[Video]Oracle Configuration Manager (OCM)Oracle Configuration Manager (OCM) works with My Oracle Support to enable proactive support capability that helps you organize, collect and manage your Oracle configurations.Oracle Configuration Manager Quick Start GuideNote 548815.1: My Oracle Support Configuration Management FAQ Note 250434.1: BULLETIN: Learn More About My Oracle Support Configuration Manager    Common Causes/Solutions The ORA-4031 can occur for many different reasons.  Some possible causes are: SGA components too small for workload Auto-tuning issues Fragmentation due to application design Bug/leaks in memory allocationsFor more on the 4031 and how this affects the SGA, see Note 396940.1 Troubleshooting and Diagnosing ORA-4031 Error Because of the multiple potential causes, it is important to gather enough diagnostics so that an appropriate solution can be identified.  However, most commonly the cause is associated with configuration tuning.   Ensuring that MEMORY_TARGET or SGA_TARGET are large enough to accommodate workload can get around many scenarios.  The default trace associated with the error provides very high level information about the memory problem and the "victim" that ran into the issue.   The data in the default trace is not going to point to the root cause of the problem. When migrating from 9i to 10g and higher, it is necessary to increase the size of the Shared Pool due to changes in the basic design of the shared memory area. Note 270935.1 Shared pool sizing in 10gNOTE: Diagnostics on the errors should be investigated as close to the time of the error(s) as possible.  If you must restart a database, it is not feasible to diagnose the problem until the database has matured and/or started seeing the problems again. Note 801787.1 Common Cause for ORA-4031 in 10gR2, Excess "KGH: NO ACCESS" Memory Allocation ***For reference to the content in this blog, refer to Note.1088239.1 Master Note for Diagnosing ORA-4031 

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• Render on other render targets starting from one already rendered on

  - by JTulip

  I have to perform a double pass convolution on a texture that is actually the color attachment of another render target, and store it in the color attachment of ANOTHER render target. This must be done multiple time, but using the same texture as starting point What I do now is (a bit abstracted, but what I have abstract is guaranteed to work singularly) renderOnRT(firstTarget); // This is working. for each other RT currRT{ glBindFramebuffer(GL_FRAMEBUFFER, currRT.frameBufferID); programX.use(); glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, firstTarget.colorAttachmentID); programX.setUniform1i("colourTexture",0); glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_2D, firstTarget.depthAttachmentID); programX.setUniform1i("depthTexture",1); glBindBuffer(GL_ARRAY_BUFFER, quadBuffID); // quadBuffID is a VBO for a screen aligned quad. It is fine. programX.vertexAttribPointer(POSITION_ATTRIBUTE, 3, GL_FLOAT, GL_FALSE, 0, (void*)0); glDrawArrays(GL_QUADS,0,4); programY.use(); glActiveTexture(GL_TEXTURE0); glBindTexture(GL_TEXTURE_2D, currRT.colorAttachmentID); // The second pass is done on the previous pass programY.setUniform1i("colourTexture",0); glActiveTexture(GL_TEXTURE1); glBindTexture(GL_TEXTURE_2D, currRT.depthAttachmentID); programY.setUniform1i("depthTexture",1); glBindBuffer(GL_ARRAY_BUFFER, quadBuffID); programY.vertexAttribPointer(POSITION_ATTRIBUTE, 3, GL_FLOAT, GL_FALSE, 0, (void*)0); glDrawArrays(GL_QUADS, 0, 4); } The problem is that I end up with black textures and not the wanted result. The GLSL programs program(X,Y) works fine, already tested on single targets. Is there something stupid I am missing? Even an hint is much appreciated, thanks!

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• Webcast: Leveraging Mobile And Social Commerce To Deliver A Complete Customer Experience

  - by Michael Hylton

    Mobile and social media are emerging as new channels for customers to interact and transact with brands. Mobile users demand experiences that are relevant and engaging and are designed with the capabilities and constraints of devices in mind. Just having a mobile app or mobile-specific website is not a long-term strategy. Brands must invest in an optimized experience, especially as mobile becomes critical to an overall digital commerce strategy.Debating the merits of using Facebook or not is missing the point when it comes to social media. True innovators are thinking beyond the social channel and are building programs that leverage Facebook data to drive conversions and engagement both on and off Facebook.  Learn how to be more strategic about mobile and social commerce in this informative editorial webcast.Attend this webcast and you will learn: How to leverage mobile and social touchpoints in digital commerce Why having a Facebook page or a mobile app is not enough The benefits of a consistent, personalized and relevant customer experience Strategies for integrating mobile and social into an overall digital commerce strategy Featured Speakers: Peter Sheldon, Senior Analyst, eBusiness & Channel Strategy Professionals, Forrester Research Brenna Johnson, Product Manager, Oracle Commerce Click here to register.

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• Webcast: Leveraging Mobile And Social Commerce To Deliver A Complete Customer Experience

  - by Michael Hylton

    Mobile and social media are emerging as new channels for customers to interact and transact with brands. Mobile users demand experiences that are relevant and engaging and are designed with the capabilities and constraints of devices in mind. Just having a mobile app or mobile-specific website is not a long-term strategy. Brands must invest in an optimized experience, especially as mobile becomes critical to an overall digital commerce strategy.Debating the merits of using Facebook or not is missing the point when it comes to social media. True innovators are thinking beyond the social channel and are building programs that leverage Facebook data to drive conversions and engagement both on and off Facebook.  Learn how to be more strategic about mobile and social commerce in this informative editorial webcast.Attend this webcast and you will learn: How to leverage mobile and social touchpoints in digital commerce Why having a Facebook page or a mobile app is not enough The benefits of a consistent, personalized and relevant customer experience Strategies for integrating mobile and social into an overall digital commerce strategy Featured Speakers: Peter Sheldon, Senior Analyst, eBusiness & Channel Strategy Professionals, Forrester Research Brenna Johnson, Product Manager, Oracle Commerce Click here to register.

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• CodePlex Daily Summary for Friday, September 14, 2012

  CodePlex Daily Summary for Friday, September 14, 2012Popular ReleasesSOAP Test Application (with EWS Tools): v0.60: Template modifications (to delete blank fields where they are not required). Bugfix for listener form where it wouldn't allow the program to be closed under certain conditions.BizTalk Zombie Management: BizTalkZombieManagement V0.1.0: First version Function supported : Listener on zombie event Dump the zombie message in folderTumblen3: tumblen3 Version14Sep2012: added 'proxy-getter' of tumblr's OAuth Access TokenIBR.StringResourceBuilder: V1.3 Release 2 Build 13: Fixed: "Making" a string resource left the table of string literals blank (due to "improvement" in Build 11). Improved: Sped up inserting resource call when "making" a string resource. from Build 12 New: Option to store all string resources in one resource file global to the project.Fruit Juice: Fruit Juice v1.0: First versionPDF Viewer Web part: PDF Viewer Web Part: PDF Viewer Web PartMicrosoft Ajax Minifier: Microsoft Ajax Minifier 4.67: Fix issue #18629 - incorrectly handling null characters in string literals and not throwing an error when outside string literals. update for Issue #18600 - forgot to make the ///#DEBUG= directive also set a known-global for the given debug namespace. removed the kill-switch for disregarding preprocessor define-comments (///#IF and the like) and created a separate CodeSettings.IgnorePreprocessorDefines property for those who really need to turn that off. Some people had been setting -kil...Active Forums for DotNetNuke CMS: Active Forums 05.00.00 RC3: Active Forums 05.00.00 RC3Lakana - WPF Framework: Lakana V2: Lakana V2 contains : - Lakana WPF Forms (with sample project) - Lakana WPF Navigation (with sample project)Microsoft SQL Server Product Samples: Database: OData QueryFeed workflow activity: The OData QueryFeed sample activity shows how to create a workflow activity that consumes an OData resource, and renders entity properties in a Microsoft Excel 2010 worksheet or Microsoft Word 2010 document. Using the sample QueryFeed activity, you can consume any OData resource. The sample activity uses LINQ to project OData metadata into activity designer expression items. By setting activity expressions, a fully qualified OData query string is constructed consisting of Resource, Filter, Or...Arduino for Visual Studio: Arduino 1.x for Visual Studio 2012, 2010 and 2008: Register for the visualmicro.com forum for more news and updates Version 1209.10 includes support for VS2012 and minor fixes for the Arduino debugger beta test team. Version 1208.19 is considered stable for visual studio 2010 and 2008. If you are upgrading from an older release of Visual Micro and encounter a problem then uninstall "Visual Micro for Arduino" using "Control Panel>Add and Remove Programs" and then run the install again. Key Features of 1209.10 Support for Visual Studio 2...Social Network Importer for NodeXL: SocialNetImporter(v.1.5): This new version includes: - Fixed the "resource limit" bug caused by Facebook - Bug fixes To use the new graph data provider, do the following: Unzip the Zip file into the "PlugIns" folder that can be found in the NodeXL installation folder (i.e "C:\Program Files\Social Media Research Foundation\NodeXL Excel Template\PlugIns") Open NodeXL template and you can access the new importer from the "Import" menuAcDown????? - AcDown Downloader Framework: AcDown????? v4.1: ??●AcDown??????????、??、??、???????。????，????，?????????????????????????。???????????Acfun、????(Bilibili)、??、??、YouTube、??、???、??????、SF????、????????????。 ●??????AcPlay?????，??????、????????????????。 ● AcDown??????????????????，????????????????????????????。 ● AcDown???????C#??，????.NET Framework 2.0??。?????"Acfun?????"。 ????32??64? Windows XP/Vista/7/8 ???? 32??64? ???Linux ????(1)????????Windows XP???,?????????.NET Framework 2.0???(x86)，?????"?????????"??? (2)???????????Linux???，????????Mono?? ??...Move Mouse: Move Mouse 2.5.2: FIXED - Minor fixes and improvements.MVC Controls Toolkit: Mvc Controls Toolkit 2.3: Added The new release is compatible with Mvc4 RTM. Support for handling Time Zones in dates. Specifically added helper methods to convert to UTC or local time all DateTimes contained in a model received by a controller, and helper methods to handle date only fileds. This together with a detailed documentation on how TimeZones are handled in all situations by the Asp.net Mvc framework, will contribute to mitigate the nightmare of dates and timezones. Multiple Templates, and more options to...DNN Metro7 style Skin package: Metro7 style Skin for DotNetNuke 06.02.00: Maintenance Release Changes on Metro7 06.02.00 Fixed width and height on the jQuery popup for the Editor. Navigation Provider changed to DDR menu Added menu files and scripts Changed skins to Doctype HTML Changed manifest to dnn6 manifest file Changed License to HTML view Fixed issue on Metro7/PinkTitle.ascx with double registering of the Actions Changed source folder structure and start folder, so the project works with the default DNN structure on developing Added VS 20...Xenta Framework - extensible enterprise n-tier application framework: Xenta Framework 1.9.0: Release Notes Imporved framework architecture Improved the framework security More import/export formats and operations New WebPortal application which includes forum, new, blog, catalog, etc. UIs Improved WebAdmin app. Reports, navigation and search Perfomance optimization Improve Xenta.Catalog domain More plugin interfaces and plugin implementations Refactoring Windows Azure support and much more... Package Guide Source Code - package contains the source code Binaries...Json.NET: Json.NET 4.5 Release 9: New feature - Added JsonValueConverter New feature - Set a property's DefaultValueHandling to Ignore when EmitDefaultValue from DataMemberAttribute is false Fix - Fixed DefaultValueHandling.Ignore not igoring default values of non-nullable properties Fix - Fixed DefaultValueHandling.Populate error with non-nullable properties Fix - Fixed error when writing JSON for a JProperty with no value Fix - Fixed error when calling ToList on empty JObjects and JArrays Fix - Fixed losing deci...DotNetNuke® Community Edition CMS: 07.00.00 CTP (Not for Production Use): NOTE: New Minimum Requirementshttp://www.dotnetnuke.com/Portals/25/Blog/Files/1/3418/Windows-Live-Writer-1426fd8a58ef_902C-MinimumVersionSupport_2.png Simplified InstallerThe first thing you will notice is that the installer has been updated. Not only have we updated the look and feel, but we also simplified the overall install process. You shouldn’t have to click through a series of screens in order to just get your website running. With the 7.0 installer we have taken an approach that a...WinRT XAML Toolkit: WinRT XAML Toolkit - 1.2.2: WinRT XAML Toolkit based on the Windows 8 RTM SDK. Download the latest source from the SOURCE CODE page. For compiled version use NuGet. You can add it to your project in Visual Studio by going to View/Other Windows/Package Manager Console and entering: PM> Install-Package winrtxamltoolkit Features AsyncUI extensions Controls and control extensions Converters Debugging helpers Imaging IO helpers VisualTree helpers Samples Recent changes NOTE: Namespace changes DebugConsol...New Projects$linq - A Javascript LINQ library: $linq is a Javascript version of .NET's Linq to Objects, with some query operations inspired by MoreLinq (an extension to Linq to Objects).AIlin: Some math operations with sparse and full matrices, elliptic curves and big numbersCapMvcHospital: Proyecto Hospital MVC para ABM de consultas clínicas y DoctoresChris on SharePoint Solutions: A collection of handy SharePoint solutions to make life easier for Site and Farm administrators.COTFACIL: O projeto visa estudar a integração web, mysql e visual studio 2010, para o estudo e conhecimento geral.Custom People Picker: The custom control which inherits the property of the "People Picker" control to display the items from the list.Data Sampler: The library allows the developer to quickly create dummy data or it can also be used to save a set of data that was originally retrieved from the database.DevelopEnvironment: ????????DotNetNuke Search Engine Sitemaps Provider: The iFinity DotNetNuke Search Engine Sitemaps Provider project generates Search Engine Sitemaps for DotNetNuke installs.Gapper Game: This is a recreation of the GAPPER DOS game that was released in 1986. The original has been abandon, so the Eastern Idaho .Net Users Group is remaking it.GestAdh45: Logiciel de gestion d'une association sportive : - gestion des adhérents/inscriptions - gestion des équipements (inventaire/vérifications)HP Printer Display Hack: A simple application that periodically checks the current price of a selected stock and sends it to the display of networked HP (and compatible) printers.INTELSI SAC: INICIOKnowledge Board Race: FATEC-SP - Engenharia de Software III KBR - Knowledge Board Race Desenvolvimento de um jogo educativo de tabuleiro on-line baseado em perguntas e respostas.MEDICALD PROJ: En este proyecto que lo haremos en equipo cada quien aportara su parte y luego la publicará aca.MVVM for Windows 8: Simple MVVM library for Windows 8.MyProjects: myprojectsNibbleOilWeb: Web Projectntcms: htcms system codingPowerConverter: PowerConverter allows you to change the old PE format to the new Power format for your PowerExtension programs.Primer Proyecto: dfrProject91404: pappapruebacodeplex: FooQuizz: D? án này là m?t ph?n c?a d? án t?t nghi?p. Vui lòng không s? d?ng vào m?c dích thuong m?i khi chua du?c s? d?ng ý c?a tác gi?.Runtime Dynamic Data Model Builder: Runtime Dynamic Data Model Builder lets you to have a Data Access Layer without writing code. It creates the database context and POCO based on Entity FrameworkSchoolProjectShitXD: Just a bunch of crap I am creating in my School,Scripture Reference Parser: Scripture Reference Parser is a library to parse data, including book, chapter, verse, and index, from references from various scriptures.Shadow: Shadow?????WCF??Remoting?ORM??，????????????????????。SharePoint Archive Tweets: Using REST, JSON and OAuth, SharePoint Archive Tweets (SPAT) was born. SPAT is a Microsoft SharePoint 2010 timer application that downloads Twitter timelines.Softech Portal - Vietnamese Portal: Gi?i pháp c?ng thông tin di?n t? thu?n Vi?t cho co quan hành chính Nhà Nu?c testdd09132012git01: sdtestdd09132012git02: ntestdd09132012hg01: dtestdd09132012tfs01: dteste tfs: testeTestRepository: Project Testing repository onlinetesttfs09132012tfs02: nThesis: This is my thesis project. It is about EDAs and Kernel classifiers. The source code is in Matlab.Tiny Contact Manager: Tiny Contact Manager manages collecting customer birthday and registration details and also sending out birthday vouchers.User Group Labs: My Groups: This is one of a series of social modules in the DotNetNuke User Group Labs project. This module allows you to easily lists the groups that a user is a part ofVatConnect: This is a Microsoft Flight Simulator add-on to connect it to the Vatsim network.Web Minesweeper with MVVM and Knockout: This is a common minesweeper game, that is implemented with mvvm in the web, only with html and javascipts libraries...Windows 8 - Using Roaming Storage in a Casual Game: This application demonstrates a simple game written for Windows 8 that illustrates how to utilize the Roaming Data Store for game data synchronization.xamlShow: This project is a demonstration of how to accomplish common tasks using WinRT XAML on Windows 8. This project is, basically, sample code used by Jerry Nixon.YTNet: YT Net is a small library which provides features for searching and downloading YouTube videos.

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• Developing an internet-enabled application as a Kiosk on Windows 7

  - by maple_shaft

  I am finalizing development of a desktop Java application that communicates with an outside web server, and now I need to start seriously considering deployment. This application will run on a large touchscreen all-in-one workstation running Windows 7. It will be located in a public-area and thus must be LOCKED-DOWN Hanibal Lecter style. Early in the project nobody really concerned themselves with this fact just assuming that we can buy some magical software for Windows 7 that will automatically take care of all this, however I am finding now that this looks to be a LOT more complicated than my manager ever thought. I need to: - Lock down the standard hot-keys (ALT+TAB, ALT+CTRL+DEL, etc...) Prevent the user from opening ANY programs other than the kiosk application and its spawned executables Prevent the user from closing the application Start the kiosk application on startup (this can be done without kiosk software) Auto-login to Windows on reboot (Windows Updates, power failure, bratty kid pressing the power button, etc...) Administrator passcode escape sequence for routine maintenance by desktop support professionals. To my dismay I am having a really hard time finding software that contains the whole package and am finding numerous swaths of competing information on the best way to do this. I am not necessarily looking for free or open source software and am willing to pay for software that can help me achieve this. Have any of you ever wrote kiosk software before and if so what approaches have you taken to do this?

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• Can't get bonding and bridging to work for KVM

  - by user9546

  Hi everyone. I can't for the life of me get bonding and bridging to work for the KVM setup I'm building. I'm using a fresh install (not an upgrade) of Ubuntu Server 10.10. I have 4 NICs on the same subnet (two intended for each of my two VMs). I'm trying to achieve the setup that Uthark describes here. But following his guidelines didn't work for me. My eth0 and eth1 did not come up, and "brctl show" showed that br0 didn't have any interfaces (the bond). I assumed it didn't work because he's using 10.4, and this article says there's a recent change in bonding: [I can't post more than one hyperlink per post because I'm a newbie.] I had to use this article to get my interfaces to work at all on the same subnet, which is why I have the post-up lines on some of my interfaces: [I can't post more than one hyperlink per post because I'm a newbie.] I installed ifenslave and ethtool. I also created /etc/modprobe.d/aliases.conf with the following content: alias bond0 bonding options bonding mode=6 miimon=100 downdelay=200 updelay=200 And I included "bonding" in /etc/modules So, after several approaches, here is my latest interfaces file: auto lo iface lo inet loopback auto eth5 iface eth5 inet manual auto br5 iface br5 inet static post-up /sbin/ip rule add from [network].79 lookup 10 post-up /sbin/ip route add table 10 default via [network].1 src [network].79 dev br5 address [network].79 netmask 255.255.255.0 network [network].0 broadcast [network].255 gateway [network].1 bridge_ports eth5 bridge_stp off bridge_fd 0 bridge_maxwait 0 auto eth2 iface eth2 inet manual auto br2 iface br2 inet static post-up /sbin/ip rule add from [network].78 lookup 11 post-up /sbin/ip route add table 11 default via [network].1 src [network].78 dev br2 address [network].78 netmask 255.255.255.0 network [network].0 broadcast [network].255 gateway [network].1 bridge_ports eth2 bridge_stp off bridge_fd 0 bridge_maxwait 0 iface eth0 inet manual iface eth1 inet manual auto bond0 iface bond0 inet static bond_miimon 100 bond_mode balance-alb up /sbin/ifenslave bond0 eth0 eth1 down /sbin/ifenslave -d bond0 eth0 eth1 auto br0 iface br0 inet static address [network].60 netmask 255.255.255.0 network [network].0 broadcast [network].255 gateway [network].1 bridge_ports bond0 eth2, eth5, br2, and br5 all seem to be working fine. The only other thing I could find that looked suspicious is an error regarding bonding in /var/log/messages: kernel: [ 3.828684] bonding: Warning: either miimon or arp_interval and arp_ip_target module parameters must be specified, otherwise bonding will not detect link failures! see bonding.txt for details. even though there is a bond-miimon line in /etc/network/interfaces (if that's what they're talking about). Also, the bond seems to go in and out of promiscuous mode several times on boot: Jan 20 14:19:02 kvmhost kernel: [ 3.902378] device bond0 entered promiscuous mode Jan 20 14:19:02 kvmhost kernel: [ 3.902390] device bond0 left promiscuous mode Jan 20 14:19:02 kvmhost kernel: [ 3.902393] device bond0 entered promiscuous mode Jan 20 14:19:02 kvmhost kernel: [ 3.902397] device bond0 left promiscuous mode Jan 20 14:19:03 kvmhost kernel: [ 4.998990] device bond0 entered promiscuous mode Jan 20 14:19:03 kvmhost kernel: [ 4.999005] device bond0 left promiscuous mode Jan 20 14:19:03 kvmhost kernel: [ 4.999008] device bond0 entered promiscuous mode Jan 20 14:19:03 kvmhost kernel: [ 4.999012] device bond0 left promiscuous mode Any advice would be greatly appreciated. It seems that this must be possible, based on other posts, but I can't see what I'm doing wrong. Thanks.

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• Is this kind of Design by Contract useless?

  - by Charlie Pigarelli

  I've just started informatics university and I'm attending a programming course about C(++). The programming professor prefers to teach very few things (in 3 month we have just reached the functions topic) and connect every topic with a type of programming design that somehow is similar to the Design by Contract design. Basically what he ask us to do is to write every exercise with comments Pre-conditions, Post-conditions and Invariants that should prove the correctness of each program we write. But this doesn't make any sense to me. I mean, ok: maybe writing down your thoughts prevent you from doing some mistakes, but if this is all an abstract thing, then if your program intuition is wrong you'll write your program wrong and then you'll also write pre and post conditions wrong probably auto convincing your self about its correctness. Most of the time, both me and other students have written programs that seemed ok and that had correct pre and post condition too. But at the moment of testing it was just completely wrong. I had some experience before this course of programming and I had written a lot of line of code before and I found myself comfortably with just writing a program and unit test it. It take less time to accomplish and is less "abstract" than just thinking about what every single piece of your program should do in every case (which is kinda like mentally testing it). Finally, all this pre and post conditions takes me like 80% of the total time of the exercise. It's harder to think about putting down this pre and post correct than to write the program itself. Since we are like the only course of the only university probably in the entire world that makes this things, could someone please tell me how should I manage this thing? Am I right thinking that this doesn't worth anything? Should I change university? (there are like double of the people attending that course and it seems that usually very few people passes the exam the first year). Should I convince myself it's method is right?

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• Installation of Tex Live via the terminal 12.04

  - by user74713

  I need to install upstream version of TeX Live for 12.04 to edit the manual for Ubuntu. I am having a difficult time installing it per the directions @ http://ubuntu-manual.org/getinvolved/editors#install-texlive. TeX Live documents are on my computer, but I am not able to run the install. No TeX Live program found on my computer. Any help is greatly appreciated! ~Thanx!~ Hello, my name is Chris. I am a student pursuing a career in technical writing. I would like to assist the Ubuntu community while gaining experience & building my resume. Below I have listed the prior attempts & links to view the posts of each attempt: Backports I have tried using the official backports of the latest (2012) TeX-Live via their PPA. Please refer to link below for the particulars. How do I install the latest 2012 TeX Live on 12.04? Latex I've also tried running Latex as suggested. Please refer to link below for the particulars. http://ubuntuforums.org/showthread.php?t=2019051 PPA Causing Issue?? or something else I came across a post concerning the ability to install programs via the terminal and am wondering if it may be my problem??? Please refer to link below for the particulars. PPA - TeX Live Cannot install anything through Terminal - apt-get -f install

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• E-Business Suite Proactive Support - Workflow Analyzer

  - by Alejandro Sosa

  Overview The Workflow Analyzer is a standalone, easy to run tool created to read, validate and troubleshoot Workflow components configuration as well as runtime. It identifies areas where potential problems may arise and based on set of best practices suggests the Workflow System Administrator what to do when such potential problems are found. This tool represents a proactive way to verify Workflow configuration and runtime data to prevent issues ahead of time before they may become of more considerable impact on a production environment. Installation Since it is standalone there are no pre-requisites and runs on Oracle E-Business applications from 11.5.10 onwards. It is installed in the back-end server and can be run directly from SQL*Plus. The output of this tool is written in a HTML file friendly formatted containing the following on both workflow Components configuration and Workflow Runtime data: Workflow-related database initialization parameters Relevant Oracle E-Business profile option values Workflow-owned concurrent programs schedule and Workflow components status Workflow notification mailer configuration and throughput via related queues and table Workflow-relevant recommended and critical one-off patches as well as current code level Workflow database footprint by reading Workflow run-time tables to identify aged processes not being purged. It also checks for large open and closed processes or unhealthy looping conditions in a workflow process, among other checks. See a sample of Workflow Analyzer's output here.  Besides performing the validations listed above, the Workflow Analyzer provides clarification on the issues it finds and refers the reader to specific Oracle MOS documents to address the findings or explains the condition for the reader to take proper action. How to get it? The Workflow Analyzer can be obtained from Oracle MOS Workflow Analyzer script for E-Business Suite Workflow Monitoring and Maintenance (Doc ID 1369938.1) and the supplemental note How to run EBS Workflow Analyzer Tool as a Concurrent Request (Doc ID 1425053.1) explains how to register and run this tool as a concurrent program. This way the report from the Workflow Analyzer can be submitted from the Application and its output can be seen from the application as well.

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• What kind of code would Kent Beck avoid unit testing?

  - by tieTYT

  I've been watching a few of the Is TDD Dead? talks on youtube, and one of the things that surprised me is Kent Beck seems to acknowledge that there are just some kinds of programs that aren't worth unit testing. For example, right here DHH says that Kent Beck is ... very happy to say "Well, TDD doesn't fit in this case, I'm just going to bail" It's frustrating to me that Kent Beck seems to acknowledge this, but nobody asks him to elaborate on it or give concrete examples. I'd like to know the situations where Kent Beck thinks TDD is a bad fit. Nobody can read his mind or speak for him, but I'm hoping he's been transparent enough through his books/tweets/whatever for someone to be able to answer. I'm not necessarily going to take what he says as gospel, but it would be useful to know that the times I've tried TDD and it just felt impossible/useless are situations that he would have bailed on it himself. Or, if it turned out he would have tested that code it'd suggest to me that I was approaching the process very wrong. I also think it would be enlightening to understand why he would bail on such projects. My opinion on why this is not a duplicate of "When is it appropriate to not unit test?" After skimming those answers I'm not satisfied. For example, look at UncleBob's answer. He doesn't even acknowledge that such a situation exists. I really think there's value in understanding Kent Beck's position, not just a general, "What's your opinion?" type of question. After all, he's the father of TDD.

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• Free Windows Store and Phone Developer Accounts for MSDN Subscribers

  - by Clint Edmonson

  If you are a member/subscriber to any of the following programs you are eligible to receive one-time, 12-month Windows Store and Windows Phone developer accounts.  Visual Studio Professional with MSDN Visual Studio Test Professional with MSDN Visual Studio Premium with MSDN Visual Studio Ultimate with MSDN BizSpark On September 11, 2012 Microsoft announced that Windows Store is open to individual developers (Company only registration became available on August 1st). This means that eligible MSDN subscribers will be able to select between an individual and company account when registering for their developer account benefit.   New or existing subscribers will see developer accounts listed as a benefit on the Getting Started page as well as various MSDN overview pages. Now that you have this benefit why not get started.  To activate this benefit, subscribers are provided with a unique token for each of the developer accounts. The tokens will work for both individual and company registration. To acquire and redeem the token: 1. Log into My Account. 2. Click on ‘Get Code’. A unique token will be delivered to each subscriber. 3. Click on ‘How to Register’ (link will appear once code is claimed). A developer account details page will display that includes an overview of the benefit, token and registration information. 4. Click on the link to ‘Register your code’.  This launches the developer account registration process. Ready to start developing?  Head over to Generation App to get started.

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• Can't install Ubuntu on my Windows 7 laptop

  - by Ana

  I tried installing Ubuntu in two different ways: First, I tried the Windows Installer, and it goes well until I reboot the system and, when booting on Ubuntu, I get the error: No root file system defined. Second, I uninstalled wubi by going to to Control Panel - Uninstall Programs - Ubuntu. Then, I booted the laptop from the live CD and selected install. It boots okay but in the screen right after the one that says to make sure you have 4.5 GB available, Internet connection, etc, when I click continue it throws me a message saying that Ubuntu had an internal error and asks me if I want to report the error. After that, I just have a black screen and nothing else! No Ubuntu installed, no boot option to go back to Windows. Nothing! My goal is to install Ubuntu alongside Windows 7 (without the hassle of formatting the computer, creating partition, etc). How can I do it (preferable using Windows Installer)? How can I solve the "No root file system defined" that I encountered when I used the Windows Installer?

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• How can I make video games if I don't like programming?

  - by hoper

  I am studying C++ code in my school (my major is computer programming). Honestly, my grades are not so good, and assignments are really hard. Sometimes I feel sad that I will spend 8-10 hours per day coding (which is stressful) in the future for my job. But I still want to make video games. Maybe this is the only reason why I am taking all of these stressful courses. I always write down plots, stories, characters, fictional gaming worlds... Once, I thought I should study artistic technology such as game design and not computer technology such as C++, C#, etc. However, most of popular game designers (or directors) such as Kojima, Miyamoto, etc. used to be good programmers. Companies actaully assign programmers to directors because they understand how to make a game. I've try to find other colleges or universities where they teach game design programs. However, one article that lists rank 10 game design schools in North America seems untrustful because the survey company only scores it from intervews of students. Once, I tried to attend Art Institute of Vancouver which is rank 7 according to that article. However, one programmer who used to be an instructor in there told me the truth: the employement rate of graduated students is low. How can I have a future making games if I don't like programming?

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• Why can't we capture the design of software more effectively?

  - by Ira Baxter

  As engineers, we all "design" artifacts (buildings, programs, circuits, molecules...). That's an activity (design-the-verb) that produces some kind of result (design-the-noun). I think we all agree that design-the-noun is a different entity than the artifact itself. A key activity in the software business (indeed, in any business where the resulting product artifact needs to be enhanced) is to understand the "design (the-noun)". Yet we seem, as a community, to be pretty much complete failures at recording it, as evidenced by the amount of effort people put into rediscovering facts about their code base. Ask somebody to show you the design of their code and see what you get. I think of a design for software as having: An explicit specification for what the software is supposed to do and how well it does it An explicit version of the code (this part is easy, everybody has it) An explanation for how each part of the code serves to achieve the specification A rationale as to why the code is the way it is (e.g., why a particualr choice rather than another) What is NOT a design is a particular perspective on the code. For example [not to pick specifically on] UML diagrams are not designs. Rather, they are properties you can derive from the code, or arguably, properties you wish you could derive from the code. But as a general rule, you can't derive the code from UML. Why is it that after 50+ years of building software, why don't we have regular ways to express this? My personal opinion is that we don't have good ways to express this. Even if we do, most of the community seems so focused on getting "code" that design-the-noun gets lost anyway. (IMHO, until design becomes the purpose of engineering, with the artifact extracted from the design, we're not going to get around this). What have you seen as means for recording designs (in the sense I have described it)? Explicit references to papers would be good. Why do you think specific and general means have not been succesful? How can we change this?

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• Empirical evidence for choice of programming paradigm to address a problem

  - by Graham Lee

  The C2 wiki has a discussion of Empirical Evidence for Object-Oriented Programming that basically concludes there is none beyond appeal to authority. This was last edited in 2008. Discussion here seems to bear this out: questions on whether OO is outdated, when functional programming is a bad choice and the advantages and disadvantages of AOP are all answered with contributors' opinions without reliance on evidence. Of course, opinions of established and reputed practitioners are welcome and valuable things to have, but they're more plausible when they're consistent with experimental data. Does this evidence exist? Is evidence-based software engineering a thing? Specifically, if I have a particular problem P that I want to solve by writing software, does there exist a body of knowledge, studies and research that would let me see how the outcome of solving problems like P has depended on the choice of programming paradigm? I know that which paradigm comes out as "the right answer" can depend on what metrics a particular study pays attention to, on what conditions the study holds constant or varies, and doubtless on other factors too. That doesn't affect my desire to find this information and critically appraise it. It becomes clear that some people think I'm looking for a "turn the crank" solution - some sausage machine into which I put information about my problem and out of which comes a word like "functional" or "structured". This is not my intention. What I'm looking for is research into how - with a lot of caveats and assumptions that I'm not going into here but good literature on the matter would - certain properties of software vary depending on the problem and the choice of paradigm. In other words: some people say "OO gives better flexibility" or "functional programs have fewer bugs" - (part of) what I'm asking for is the evidence of this. The rest is asking for evidence against this, or the assumptions under which these statements are true, or evidence showing that these considerations aren't important. There are plenty of opinions on why one paradigm is better than another; is there anything objective behind any of these?

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• How best to deal with the frustration that you encounter at the beginning of learning to code [closed]

  - by coderboy

  I am right now a newbie on the job learning to code in Cocoa . In the beginning I decided that I would try and understand everything I was doing . But right now I just feel like a clueless wizard chanting some spells . Its all just a matter of googling the right incantation . Frequently getting stuck and having to google for answers is proving to be a major demotivator for me . I know that this will get better over time but still I feel that somewhere , somehow I'm just approaching things the wrong way . I sit there stumped and then finally just look at sample code from Apple and I go Wow ! This is so logical and well structured ! . But just reading it is not going to get me to that level . So I would like to know , how do you guys approach learning something new . Do you read the whole documentation first , or do you read sample code or maybe its just about making lots of small programs first ?

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• The How-To Geek Video Guide to Using Windows 7 Speech Recognition

  - by YatriTrivedi

  Ever get the desire to control your computer, Star Trek-style? With Windows 7’s Speech Recognition, it’s easier than you might think. Microsoft has been working on its voice command steadily over the years. XP introduced it, Vista smoothed it, and 7 has it polished. It’s strangely not advertised as a feature, even though other voice command and speech recognition programs are hundreds of dollars. It may not be as perfect as some of them, but there’s definitely something amazing about vocally telling your computer to do things and it actually working Latest Features How-To Geek ETC How To Create Your Own Custom ASCII Art from Any Image How To Process Camera Raw Without Paying for Adobe Photoshop How Do You Block Annoying Text Message (SMS) Spam? How to Use and Master the Notoriously Difficult Pen Tool in Photoshop HTG Explains: What Are the Differences Between All Those Audio Formats? How To Use Layer Masks and Vector Masks to Remove Complex Backgrounds in Photoshop Bring Summer Back to Your Desktop with the LandscapeTheme for Chrome and Iron The Prospector – Home Dash Extension Creates a Whole New Browsing Experience in Firefox KinEmote Links Kinect to Windows Why Nobody Reads Web Site Privacy Policies [Infographic] Asian Temple in the Snow Wallpaper 10 Weird Gaming Records from the Guinness Book

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• My processor is not detected intel core 2 duo

  - by walid

  My processor is not detected intel core 2 duo When I type $uname -m -p I get this i686 unknown I have Ubuntu 10.10 netbook remix but the cat /proc/cpuinfo gives right identification of two processors as below processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Core(TM)2 CPU T5600 @ 1.83GHz stepping : 6 cpu MHz : 1826.000 cache size : 2048 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 2 apicid : 0 initial apicid : 0 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm lahf_lm dts tpr_shadow bogomips : 3657.99 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Core(TM)2 CPU T5600 @ 1.83GHz stepping : 6 cpu MHz : 1826.000 cache size : 2048 KB physical id : 0 siblings : 2 core id : 1 cpu cores : 2 apicid : 1 initial apicid : 1 fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm lahf_lm dts tpr_shadow bogomips : 3657.53 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: The problem is with programs that uses more than one core like virtualbox and bitcoin which refuses to use more than one core Is there anythign wrong or anything that I can do? My installation is from a live usb iso on a USB

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• HPCM 11.1.2.2.x - HPCM Standard Costing Generating >99 Calc Scipts

  - by Jane Story

  HPCM Standard Profitability calculation scripts are named based on a documented naming convention. From 11.1.2.2.x, the script name = a script suffix (1 letter) + POV identifier (3 digits) + Stage Order Number (1 digit) + “_” + index (2 digits) (please see documentation for more information (http://docs.oracle.com/cd/E17236_01/epm.1112/hpm_admin/apes01.html). This naming convention results in the name being 8 characters in length i.e. the maximum number of characters permitted calculation script names in non-unicode Essbase BSO databases. The index in the name will indicate the number of scripts per stage. In the vast majority of cases, the number of scripts generated per stage will be significantly less than 100 and therefore, there will be no issue. However, in some cases, the number of scripts generated can exceed 99. It is unusual for an application to generate more than 99 calculation scripts for one stage. This may indicate that explicit assignments are being extensively used. An assessment should be made of the design to see if assignment rules can be used instead. Assignment rules will reduce the need for so many calculation script lines which will reduce the requirement for such a large number of calculation scripts. In cases where the scripts generates exceeds 100, the length of the name of the 100th calculation script is different from the 99th as the calculation script name changes from being 8 characters long and becomes 9 characters long (e.g. A6811_100 rather than A6811_99). A name of 9 characters is not permitted in non Unicode applications. It is “too long”. When this occurs, an error will show in the hpcm.log as “Error processing calculation scripts” and “Unexpected error in business logic “. Further down the log, it is possible to see that this is “Caused by: Error copying object “ and “Caused by: com.essbase.api.base.EssException: Cannot put olap file object ... object name_[<calc script name> e.g. A6811_100] too long for non-unicode mode application”. The error file will give the name of the calculation script which is causing the issue. In my example, this is A6811_100 and you can see this is 9 characters in length. It is not possible to increase the number of characters allowed in a calculation script name. However, it is possible to increase the size of each calculation script. The default for an HPCM application, set in the preferences, is set to 4mb. If the size of each calculation script is larger, the number of scripts generated will reduce and, therefore, less than 100 scripts will be generated which means that the name of the calculation script will remain 8 characters long. To increase the size of the generated calculation scripts for an application, in the HPM_APPLICATION_PREFERENCE table for the application, find the row where HPM_PREFERENCE_NAME_ID=20. The default value in this row is 4194304. This can be increased e.g. 7340032 will increase this to 7mb. Please restart the profitability service after making the change.

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• Alternatives for the Snippet Compiler

  - by Marko Apfel

  It seems that the Snippet Compiler is not maintained anymore. So I need an alternative – also for getting syntax highlighting for code in publications. Preferable with the possibility to conserve this highlighting by copying selections to clipboard. Snippet Compiler does not allows this for selections – only by exporting the whole file content to clipboard with HTML- or RTF-formatting (File > Export > HTML to clipboard respectively RTF to clipboard). Today I switched to LINQPad. This application offers constructing LINQ-statements as well as compiling arbitrary code snippets. But there are some other alternatives too: CS-Script - The C# Script Engine CS-Script is a CLR (Common Language Runtime) based scripting system which uses ECMA-compliant C# as a programming language. CS-Script currently targets Microsoft implementation of CLR (.NET 2.0/3.0/3.5. sharpsnippetcompiler C# Snippet Compiler is a tiny IDE to create, debug and run your C# programs CsharpRepl C# interactive shell that is part of Mono's C# compiler. An interactive shell is usually referred to as a read eval print loop or repl. The C# interactive shell is built on top of the Mono.CSharp library, a library that provides a C# compiler service that can be used to evaluate expressions and statements on the flight. What I miss is an alternative with syntax highlighting like in my Visual Studio: Instead of:

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• Type checking and recursive types (Writing the Y combinator in Haskell/Ocaml)

  - by beta

  When explaining the Y combinator in the context of Haskell, it's usually noted that the straight-forward implementation won't type-check in Haskell because of its recursive type. For example, from Rosettacode [1]: The obvious definition of the Y combinator in Haskell canot be used because it contains an infinite recursive type (a = a -> b). Defining a data type (Mu) allows this recursion to be broken. newtype Mu a = Roll { unroll :: Mu a -> a } fix :: (a -> a) -> a fix = \f -> (\x -> f (unroll x x)) $ Roll (\x -> f (unroll x x)) And indeed, the “obvious” definition does not type check: ?> let fix f g = (\x -> \a -> f (x x) a) (\x -> \a -> f (x x) a) g <interactive>:10:33: Occurs check: cannot construct the infinite type: t2 = t2 -> t0 -> t1 Expected type: t2 -> t0 -> t1 Actual type: (t2 -> t0 -> t1) -> t0 -> t1 In the first argument of `x', namely `x' In the first argument of `f', namely `(x x)' In the expression: f (x x) a <interactive>:10:57: Occurs check: cannot construct the infinite type: t2 = t2 -> t0 -> t1 In the first argument of `x', namely `x' In the first argument of `f', namely `(x x)' In the expression: f (x x) a (0.01 secs, 1033328 bytes) The same limitation exists in Ocaml: utop # let fix f g = (fun x a -> f (x x) a) (fun x a -> f (x x) a) g;; Error: This expression has type 'a -> 'b but an expression was expected of type 'a The type variable 'a occurs inside 'a -> 'b However, in Ocaml, one can allow recursive types by passing in the -rectypes switch: -rectypes Allow arbitrary recursive types during type-checking. By default, only recursive types where the recursion goes through an object type are supported. By using -rectypes, everything works: utop # let fix f g = (fun x a -> f (x x) a) (fun x a -> f (x x) a) g;; val fix : (('a -> 'b) -> 'a -> 'b) -> 'a -> 'b = <fun> utop # let fact_improver partial n = if n = 0 then 1 else n*partial (n-1);; val fact_improver : (int -> int) -> int -> int = <fun> utop # (fix fact_improver) 5;; - : int = 120 Being curious about type systems and type inference, this raises some questions I'm still not able to answer. First, how does the type checker come up with the type t2 = t2 -> t0 -> t1? Having come up with that type, I guess the problem is that the type (t2) refers to itself on the right side? Second, and perhaps most interesting, what is the reason for the Haskell/Ocaml type systems to disallow this? I guess there is a good reason since Ocaml also will not allow it by default even if it can deal with recursive types if given the -rectypes switch. If these are really big topics, I'd appreciate pointers to relevant literature. [1] http://rosettacode.org/wiki/Y_combinator#Haskell

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