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• CodePlex Daily Summary for Wednesday, September 12, 2012

  CodePlex Daily Summary for Wednesday, September 12, 2012Popular ReleasesActive Forums for DotNetNuke CMS: Active Forums 05.00.00 RC2: Active Forums 05.00.00 RC2SSIS Compressed File Source and Destination Components: Compressed File Souce and Destination Components: Initial Beta ReleaseArduino 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...Bookmark Collector: 01.01.00: This release has the follow new features and updates: Enhanced the ContentItem integration Changed the format of how ContentItem content is saved Implemented core JSON methods from the API Fully documented the source code Please Note: This module was originally written as a proof of concept for how to create a simple module using the Christoc module templates, and using the ContentItems API instead of a DAL. Minimum Requirements DotNetNuke v06.02.03 or newer .Net Framework v3.5 SP1...Microsoft Script Explorer for Windows PowerShell: Script Explorer Reference Implementation(s): This download contains Source Code and Documentation for Script Explorer DB Reference Implementation. You can create your own provider and use it in Script Explorer. Refer to the documentation for more information. The source code is provided "as is" without any warranty. Read the Readme.txt file in the SourceCode.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...Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.66: Just going to bite the bullet and rip off the band-aid... SEMI-BREAKING CHANGE! Well, it's a BREAKING change to those who already adjusted their projects to use the previous breaking change's ill-conceived renamed DLLs (versions 4.61-4.65). For those who had not adapted and were still stuck in this-doesn't-work-please-fix-me mode, this is more like a fixing change. The previous breaking change just broke too many people, I'm sorry to say. Renaming the DLL from AjaxMin.dll to AjaxMinLibrary.dl...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...BIDS Helper: BIDS Helper 1.6.1: In addition to fixing a number of bugs that beta testers reported, this release includes the following new features for Tabular models in SQL 2012: New Features: Tabular Display Folders Tabular Translations Editor Tabular Sync Descriptions Fixed Issues: Biml issues 32849 fixing bug in Tabular Actions Editor Form where you type in an invalid action name which is a reserved word like CON or which is a duplicate name to another action 32695 - fixing bug in SSAS Sync Descriptions whe...Code Snippets for Windows Store Apps: Code Snippets for Windows Store Apps: First release of our snippets! For more information: Installation List of SnippetsUmbraco CMS: Umbraco 4.9.0: Whats newThe media section has been overhauled to support HTML5 uploads, just drag and drop files in, even multiple files are supported on any HTML5 capable browser. The folder content overview is also much improved allowing you to filter it and perform common actions on your media items. The Rich Text Editor’s “Media” button now uses an embedder based on the open oEmbed standard (if you’re upgrading, enable the media button in the Rich Text Editor datatype settings and set TidyEditorConten...WordMat: WordMat v. 1.02: This version was used for the 2012 exam.menu4web: menu4web 0.4.1 - javascript menu for web sites: This release is for those who believe that global variables are evil. menu4web has been wrapped into m4w singleton object. Added "Vertical Tabs" example which illustrates object notation.New Projects[ITFA GROUP] CODE GENER: Code Gener is a tool to help programmers and system builders in building applications. ANPR MX: ANPR MX is a simple Automatic Plate Recognition (ANPR) library for the North American average plate size based on C# and OpenCV. BatteryStatus: show battery level on status bar on an android deviceCode Snippets for Windows Store Apps: Code Snippets for Windows Store apps is a collection of around 60 IntelliSense Code Snippets for Visual Basic, C#, C++, and JavaScript developers.Cube2d: cube2dDiscover_U_Server: Discover_U_ServerExeLauncher: Make PATH recursiveExpression Evaluator + aggregate functions support: Simple library for expressions evaluation that supports variables in expression and aggregative functions to parse and evaluate expression against tabular data.FancyGrid: A custom datagrid for WPF with support for real-time filtering, multisort, and themes. Compatible with MVVM and normal WPF binding.langben: ??????????????，?????????????，??，???????，?????，???????，?????????????????????????。 ???? •????????（SOA） •????????????????? •?????????????? •??IE 6、IE 8+?FirefMakeTracks Gadgeteer GPS Module Driver: This project is the driver for the Gadgeteer compatible MakeTracks GPS module developed by Eric Hall and other members of the tinyclr.com community.MyCloud: heheOVS: OVS est un projet d'analyse et de traitement de signaux Vidéo sur IP avec remontées d'informations sur consultables sur des terminaux mobilesPMS: Project Management System for HSUScenario4: testSharePoint 2010 Syntax Highlighting: This project allows users to apply syntax highlighting to code snippits via the SharePoint 2010 Ribbon UI.SharePoint CRM: CRM/Project Management Site template for both SharePoint 2010 Enterprise and Office 365 Enterprise tennantsSharePoint PowerShell Wizard: The SharePoint PowerShell Wizards provides a tool to help generate and support some of the PowerShell scripts needed to recreate aspects of your farm.Shindo's Race System: Shindo's Race System is a plugin for SA:MP Dedicated Server 0.3e.Test MVC application: Test project - please ignore!weber: Weber is a private browser, it tries to prevent the user from being tracked by the advertisers and traffic monitoring sites. Hence it is severely impaired. Try!xuebin: web site

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• Collocation in Code

  - by Dan McGrath

  Quite some time ago I remember reading an article from 'Joel on Software' that mentioned collocation of information in code was important. By collocation, I mean that relevant information about the code is present when the code is. I'm currently writing an article that has a small bit in it about collocation so I went searching for sources and found the quote in the article 'Making Wrong Code Look Wrong' In order to make code really, really robust, when you code-review it, you need to have coding conventions that allow collocation. In other words, the more information about what code is doing is located right in front of your eyes, the better a job you’ll do at finding the mistakes. When you have code that says For me, collocation isn't just about the code itself, but the tool used to view the code. If it can help with the 'collocation factor' (term coined by me?) I believe it can help with the programmers productivity. Take for example the modern IDEs that show you the variables type by hovering over it. Are their any other articles written about collocation in code and/or are their other terms that this is known by?

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• Implementing a post-notification function to perform custom validation

  - by Alejandro Sosa

  Introduction Oracle Workflow Notification System can be extended to perform extra validation or processing via PLSQL procedures when the notification is being responded to. These PLSQL procedures are called post-notification functions since they are executed after a notification action such as Approve, Reject, Reassign or Request Information is performed. The standard signature for the post-notification function is     procedure <procedure_name> (itemtype  in varchar2,                                itemkey   in varchar2,                                actid     in varchar2,                                funcmode  in varchar2,                                resultout in out nocopy varchar2); Modes The post-notification function provides the parameter 'funcmode' which will have the following values: 'RESPOND', 'VALIDATE, and 'RUN' for a notification is responded to (Approve, Reject, etc) 'FORWARD' for a notification being forwarded to another user 'TRANSFER' for a notification being transferred to another user 'QUESTION' for a request of more information from one user to another 'QUESTION' for a response to a request of more information 'TIMEOUT' for a timed-out notification 'CANCEL' when the notification is being re-executed in a loop. Context Variables Oracle Workflow provides different context information that corresponds to the current notification being acted upon to the post-notification function. WF_ENGINE.context_nid - The notification ID  WF_ENGINE.context_new_role - The new role to which the action on the notification is directed WF_ENGINE.context_user_comment - Comments appended to the notification   WF_ENGINE.context_user - The user who is responsible for taking the action that updated the notification's state WF_ENGINE.context_recipient_role - The role currently designated as the recipient of the notification. This value may be the same as the value of WF_ENGINE.context_user variable, or it may be a group role of which the context user is a member. WF_ENGINE.context_original_recipient - The role that has ownership of and responsibility for the notification. This value may differ from the value of the WF_ENGINE.context_recipient_role variable if the notification has previously been reassigned.  Example Let us assume there is an EBS transaction that can only be approved by a certain people thus any attempt to transfer or delegate such notification should be allowed only to users SPIERSON or CBAKER. The way to implement this functionality would be as follows: Edit the corresponding workflow definition in Workflow Builder and open the notification. In the Function Name enter the name of the procedure where the custom code is handled, for instance, TEST_PACKAGE.Post_Notification In PLSQL create the corresponding package TEST_PACKAGE with a procedure named Post_Notification, as follows:     procedure Post_Notification (itemtype  in varchar2,                                  itemkey   in varchar2,                                  actid     in varchar2,                                  funcmode  in varchar2,                                  resultout in out nocopy varchar2) is     l_count number;     begin       if funcmode in ('TRANSFER','FORWARD') then         select count(1) into l_count         from WF_ROLES         where WF_ENGINE.context_new_role in ('SPIERSON','CBAKER');               --and/or any other conditions         if l_count<1 then           WF_CORE.TOKEN('ROLE', WF_ENGINE.context_new_role);           WF_CORE.RAISE('WFNTF_TRANSFER_FAIL');         end if;       end if;     end Post_Notification; Launch the workflow process with the changed notification and attempt to reassign or transfer it. When trying to reassign the notification to user CBROWN the screen would like like below: Check the Workflow API Reference Guide, section Post-Notification Functions, to see all the standard, seeded WF_ENGINE variables available for extending notifications processing. 

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• Limiting game loop to exactly 60 tics per second (Android / Java)

  - by user22241

  So I'm having terrible problems with stuttering sprites. My rendering and logic takes less than a game tic (16.6667ms) However, although my game loop runs most of the time at 60 ticks per second, it sometimes goes up to 61 - when this happens, the sprites stutter. Currently, my variables used are: //Game updates per second final int ticksPerSecond = 60; //Amount of time each update should take final int skipTicks = (1000 / ticksPerSecond); This is my current game loop @Override public void onDrawFrame(GL10 gl) { // TODO Auto-generated method stub //This method will run continuously //You should call both 'render' and 'update' methods from here //Set curTime initial value if '0' //Set/Re-set loop back to 0 to start counting again loops=0; while(System.currentTimeMillis() > nextGameTick && loops < maxFrameskip){ SceneManager.getInstance().getCurrentScene().updateLogic(); //Time correction to compensate for the missing .6667ms when using int values nextGameTick+=skipTicks; timeCorrection += (1000d/ticksPerSecond) % 1; nextGameTick+=timeCorrection; timeCorrection %=1; //Increase loops loops++; } render(); } I realise that my skipTicks is an int and therefore will come out as 16 rather that 16.6667 However, I tried changing it (and ticksPerSecond) to Longs but got the same problem). I also tried to change the timer used to Nanotime and skiptics to 1000000000/ticksPerSecond, but everything just ran at about 300 ticks per seconds. All I'm attempting to do is to limit my game loop to 60 - what is the best way to guarantee that my game updates never happen at more than 60 times a second? Please note, I do realise that very very old devices might not be able to handle 60 although I really don't expect this to happen - I've tested it on the lowest device I have and it easily achieves 60 tics. So I'm not worried about a device not being able to handle the 60 ticks per second, but rather need to limit it - any help would be appreciated.

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• How to install Oracle Database 11g Express Edition on Ubuntu 12.10?

  - by Praneeth Pj

  I installed the Oracle database following the steps mentioned in this blog. Downloaded 11g express edition Created a new user oracle under the group dba. Following steps are executed using this. Unzipped oracle-xe-11.2.0-1.0.x86_64.rpm.zip and then converted the rpm to the Ubuntu package by running: sudo alien --scripts -d oracle-xe-11.2.0-1.0.x86_64.rpm Created /sbin/chkconfig file and added the entries as specified there. Created /etc/sysctl.d/60-oracle.conf and added the entries as specified in the same link as above. Running the commands: ln -s /usr/bin/awk /bin/awk mkdir /var/lock/subsys touch /var/lock/subsys/listener .deb generated in step 3: sudo dpkg --install oracle-xe_11.2.0-2_amd64.deb Left the default values as it is: sudo /etc/init.d/oracle-xe configure Set the following env variables in ~/.bashrc file: export ORACLE_HOME=/u01/app/oracle/product/11.2.0/xe export ORACLE_SID=XE export NLS_LANG=`$ORACLE_HOME/bin/nls_lang.sh` export ORACLE_BASE=/u01/app/oracle export LD_LIBRARY_PATH=$ORACLE_HOME/lib:$LD_LIBRARY_PATH export PATH=$ORACLE_HOME/bin:$PATH Running the commands: chown -R oracle:dba /var/tmp/.oracle chmod -R 755 /var/tmp/.oracle chown -R oracle:dba /tmp/.oracle chmod -R 755 /tmp/.oracle Starting Oracle Database 11g Express Edition instance: sudo service oracle-xe start sqlplus / as sysdba and got the following: SQL*Plus: Release 11.2.0.2.0 Production on Thu Jan 3 09:41:58 2013 Copyright (c) 1982, 2011, Oracle. All rights reserved. Connected to an idle instance. Now when exectuting any SQL statements on SQLplus, I end up with the following error: SQL> select * from dual; select * from dual * ERROR at line 1: ORA-01034: ORACLE not available Process ID: 0 Session ID: 0 Serial number: 0 I have increased the swap memory as specified here $ free -m total used free shared buffers cached Mem: 3901 3428 473 0 182 1988 -/+ buffers/cache: 1258 2643 Swap: 5066 0 5066

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• How to write a very basic compiler [closed]

  - by Ali

  Possible Duplicate: Best Online resources to learn about Compilers? What would be the best way to learn about compilers, and executable formats? Advanced compilers like gcc compile codes into machine readable files according to the language in which the code has been written (e.g. C, C++, etc). In fact, they interpret the meaning of each codes according to library and functions of the corresponding languages. Correct me if I'm wrong. I wish to better understand compilers by writing a very basic compiler (probably in C) to compile a static file (e.g. Hello World in a text file). I tried some tutorials and books, but all of them are for practical cases. They deal with compiling dynamic codes with meanings connected with the corresponding language. How can I write a basic compiler to convert a static text into a machine readable file? The next step will be introducing variables into the compiler; imagine that we want to write a compiler which compile only some functions of a language. Introducing practical tutorials and resources is highly appreciated :-)

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• Oracle Warehouse Builder és Enterprise ETL

  - by Fekete Zoltán

  Friss és ropogós az adatlap!!! Fogyasszátok egészséggel: ODI Enterprise Edition: Warehouse Builder Enterprise ETL white paper. A jó hír: minden megvásárolt Oracle Database-hez ingyenese használható az Oracle Warehouse Builder alap (core) funkcionalitása. Mi is az az OWB core funkcionalitás, és mit használhatunk az opciókban? Az Enterprise ETL funkcionalitás az Oracle Data Integrator Enterprise Edition licensz részeként érheto el az OWB-hez. Azok a funkciók, amik csak az ODI EE licensszel érhetok el (a korábbi OWB Enterprise ETL opció is ennek a része) megtekinthetok itt is a szöveg alján. Ezek: - Transportable ETL modules, multiple configurations, and pluggable mappings - Operators for pluggable mapping, pluggable mapping input signature, pluggable mapping output signature - Design Environment Support for RAC - Metadata change propagation - Schedulable Mappings and Process Flows - Slowing Changing Dimensions (SCD) Type 2 and 3 - XML Files as a target - Target load ordering - Seeded spatial and streams transformations - Process Flow Activity templates - Process Flow variables support - Process Flow looping activities such as For Loop and While Loop - Process Flow Route and Notification activities - Metadata lineage and impact analysis - Metadata Extensibility - Deployment to Discoverer EUL - Deployment to Oracle BI Beans catalog Tehát ha komolyabb környezetben szeretném használni az OWB-t, több környezetbe deployálni, stb, akkor szükség van az ODI EE licenszre is. ODI Enterprise Edition: Warehouse Builder Enterprise ETL white paper.

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• Tracking state of a one time event on a big website

  - by Mattis

  Assume a website with 250 million active users. I add a new feature to the website. Once a user visits I want to use a short tutorial to teach them how to use said feature. I only want them to complete the tutorial once (or actively click it away). What is the smart way to code the verification check for this? How do I track the progress in the database? Having a separate table with like NewTutorial_completed = 1 for user_id = 21312315 would just snowball. It also feels intuitively bad to check for every one-time event for every user on every page view. While writing the question I got one idea, to have a separate event log that is checked periodically for any new action the user need to see or perform. I push events to this log and once they are completed they are removed from the log. No need to store NewTutorial_completed = 1-type variables this way. I am sure this is a common problem. I would appreciate any input on what best practice is.

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• From physics to Java programmer?

  - by inovaovao

  I'm a physics phd with little actual programming experience. I've always liked programming and played around with Basic and Pascal (also VB and Delphi) as a teen, but the largest actual project I completed was an assignement for the introductory computer science class in university where I wrote a nice little program (about 1500 lines of pascal) to display functions of 2 variables in 3D. I've had also a couple other projects of a few hundred lines range, but during my phd I didn't have (or take) the time to program more (string theory is hard guys!), beside playing around with ruby. Now I've decided that I'm more interested in programming than in physics and started to learn Java (hoping to pass the certification exam next week) and OO design. Still, I have trouble deciding on what to focus next (Java EE? Web development? algorithms and C programming?) in order to maximize my employement chances. Bear in mind that I'm aiming (mostly) at the swedish job market and that I'm 30 years old. So for the questions: Do you think that I have any chances to start and make a career in IT and programming coming from physics? What would be the best strategy to maximize my value in the field? Do you have suggestions as to where my physics background might be useful?

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• SQL SERVER – Using MAXDOP 1 for Single Processor Query – SQL in Sixty Seconds #008 – Video

  - by pinaldave

  Today’s SQL in Sixty Seconds video is inspired from my presentation at TechEd India 2012 on Speed up! – Parallel Processes and Unparalleled Performance. There are always special cases when it is about SQL Server. There are always few queries which gives optimal performance when they are executed on single processor and there are always queries which gives optimal performance when they are executed on multiple processors. I will be presenting the how to identify such queries as well what are the best practices related to the same. In this quick video I am going to demonstrate if the query is giving optimal performance when running on single CPU how one can restrict queries to single CPU by using hint OPTION (MAXDOP 1). More on Errors: Difference Temp Table and Table Variable – Effect of Transaction Effect of TRANSACTION on Local Variable – After ROLLBACK and After COMMIT Debate – Table Variables vs Temporary Tables – Quiz – Puzzle – 13 of 31 I encourage you to submit your ideas for SQL in Sixty Seconds. We will try to accommodate as many as we can. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Database, Pinal Dave, PostADay, SQL, SQL Authority, SQL in Sixty Seconds, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Video

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• The problems with Avoiding Smurf Naming classes with namespaces

  - by Daniel Koverman

  I pulled the term smurf naming from here (number 21). To save anyone not familiar the trouble, Smurf naming is the act of prefixing a bunch of related classes, variables, etc with a common prefix so you end up with "a SmurfAccountView passes a SmurfAccountDTO to the SmurfAccountController", etc. The solution I've generally heard to this is to make a smurf namespace and drop the smurf prefixes. This has generally served me well, but I'm running into two problems. I'm working with a library with a Configuration class. It could have been called WartmongerConfiguration but it's in the Wartmonger namespace, so it's just called Configuration. I likewise have a Configuration class which could be called SmurfConfiguration, but it is in the Smurf namespace so that would be redundant. There are places in my code where Smurf.Configuration appears alongside Wartmonger.Configuration and typing out fully qualified names is clunky and makes the code less readable. It would be nicer to deal with a SmurfConfiguration and (if it was my code and not a library) WartmongerConfiguration. I have a class called Service in my Smurf namespace which could have been called SmurfService. Service is a facade on top of a complex Smurf library which runs Smurf jobs. SmurfService seems like a better name because Service without the Smurf prefix is so incredibly generic. I can accept that SmurfService was already a generic, useless name and taking away smurf merely made this more apparent. But it could have been named Runner, Launcher, etc and it would still "feel better" to me as SmurfLauncher because I don't know what a Launcher does, but I know what a SmurfLauncher does. You could argue that what a Smurf.Launcher does should be just as apparent as a Smurf.SmurfLauncher, but I could see `Smurf.Launcher being some kind of class related to setup rather than a class that launches smurfs. If there is an open and shut way to deal with either of these that would be great. If not, what are some common practices to mitigate their annoyance?

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• How to determine if you should use full or differential backup?

  - by Peter Larsson

  Or ask yourself, "How much of the database has changed since last backup?". Here is a simple script that will tell you how much (in percent) have changed in the database since last backup. -- Prepare staging table for all DBCC outputs DECLARE @Sample TABLE         (             Col1 VARCHAR(MAX) NOT NULL,             Col2 VARCHAR(MAX) NOT NULL,             Col3 VARCHAR(MAX) NOT NULL,             Col4 VARCHAR(MAX) NOT NULL,             Col5 VARCHAR(MAX)         )   -- Some intermediate variables for controlling loop DECLARE @FileNum BIGINT = 1,         @PageNum BIGINT = 6,         @SQL VARCHAR(100),         @Error INT,         @DatabaseName SYSNAME = 'Yoda'   -- Loop all files to the very end WHILE 1 = 1     BEGIN         BEGIN TRY             -- Build the SQL string to execute             SET     @SQL = 'DBCC PAGE(' + QUOTENAME(@DatabaseName) + ', ' + CAST(@FileNum AS VARCHAR(50)) + ', '                             + CAST(@PageNum AS VARCHAR(50)) + ', 3) WITH TABLERESULTS'               -- Insert the DBCC output in the staging table             INSERT  @Sample                     (                         Col1,                         Col2,                         Col3,                         Col4                     )             EXEC    (@SQL)               -- DCM pages exists at an interval             SET    @PageNum += 511232         END TRY           BEGIN CATCH             -- If error and first DCM page does not exist, all files are read             IF @PageNum = 6                 BREAK             ELSE                 -- If no more DCM, increase filenum and start over                 SELECT  @FileNum += 1,                         @PageNum = 6         END CATCH     END   -- Delete all records not related to diff information DELETE FROM    @Sample WHERE   Col1 NOT LIKE 'DIFF%'   -- Split the range UPDATE  @Sample SET     Col5 = PARSENAME(REPLACE(Col3, ' - ', '.'), 1),         Col3 = PARSENAME(REPLACE(Col3, ' - ', '.'), 2)   -- Remove last paranthesis UPDATE  @Sample SET     Col3 = RTRIM(REPLACE(Col3, ')', '')),         Col5 = RTRIM(REPLACE(Col5, ')', ''))   -- Remove initial information about filenum UPDATE  @Sample SET     Col3 = SUBSTRING(Col3, CHARINDEX(':', Col3) + 1, 8000),         Col5 = SUBSTRING(Col5, CHARINDEX(':', Col5) + 1, 8000)   -- Prepare data outtake ;WITH cteSource(Changed, [PageCount]) AS (     SELECT      Changed,                 SUM(COALESCE(ToPage, FromPage) - FromPage + 1) AS [PageCount]     FROM        (                     SELECT CAST(Col3 AS INT) AS FromPage,                             CAST(NULLIF(Col5, '') AS INT) AS ToPage,                             LTRIM(Col4) AS Changed                     FROM    @Sample                 ) AS d     GROUP BY    Changed     WITH ROLLUP ) -- Present the final result SELECT  COALESCE(Changed, 'TOTAL PAGES') AS Changed,         [PageCount],         100.E * [PageCount] / SUM(CASE WHEN Changed IS NULL THEN 0 ELSE [PageCount] END) OVER () AS Percentage FROM    cteSource

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• LibGdx efficient data saving/loading?

  - by grimrader22

  Currently, my LibGDX game consists of a 512 x 512 map of Tiles and entities such as players and monsters. I am wondering how to efficiently save and load the data of my levels. At the moment I am using JSON serialization for each class I want to save. I implement the Json.Serializable interface for all of these classes and write only the variables that are necessary. So my map consists of 512 x 512 tiles, that's 260,000 tiles. Each tile on the map consists of a Tile object, which points to some final Tile object like a GRASS_TILE or a STONE_TILE. When I serialize each level tile, the final Tile that it points to is re-serialized over and over again, so if I have 100 Tiles all pointing to GRASS_TILE, the data of GRASS_TILE is written 100 times over. When I go to load/deserialize my objects, 100 GrassTile objects are created, but they are each their own object. They no longer point to the final tile object. I feel like this reading/writing files very slow. If I were to abandon JSON serialization, to my knowledge my next best option would be saving the level data to a sql database. Unless there is a way to speed up serializing/deserializing 260,000 tiles I may have to do this. Is this a good idea? Could I really write that many tiles to the database efficiently? To sum all this up, I am trying to save my levels using JSON serialization, but it is VERY slow. What other options do I have for saving the data of so many tiles. I also must note that the JSON serialization is not slow on a PC, it is only VERY slow on a mobile device. Since file writing/reading is so slow on mobile devices, what can I do?

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• My first animation - Using SDL.NET C#

  - by Mark

  Hi all! I'm trying to animate a player object in my 2D grid when the user clicks somewhere in the screen. I got the following 4 variables: oX (Current player position X) oY (Current player position Y) dX (Destination X) dY (Destination Y) How can I make sure the player moves in a straight line to the new XY coordinates. The way I'm doing it now is really awfull and causes the player to first move along x axis, and finally in y axis. Can someone give me some guidance with the involved math cause I'm really not sure on how to accomplish this. Thank you for your time. Kind regards, Mark Update: It's working now but whats the right way to check if the current positions are equal to the target position? private static void MovePlayer(double x2, double y2, int duration) { double hX = x2 - m_PlayerPosition.X; double hY = y2 - m_PlayerPosition.Y; double Length = Math.Sqrt(Math.Pow(hX, 2) + Math.Pow(hY, 2)); hX = hX / Length; hY = hY / Length; while (m_PlayerPosition.X != Convert.ToInt32(x2) || m_PlayerPosition.Y != Convert.ToInt32(y2)) { m_PlayerPosition.X += Convert.ToInt32(hX * 1); m_PlayerPosition.Y += Convert.ToInt32(hY * 1); UpdatePlayerLocation(); } }

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• Unit Tests as a learning tool - a good idea?

  - by Ekkehard.Horner

  I'm interested in ways and means for learning (a) programming language(s) efficiently. I believe that using Unit Test concepts and infrastructure early in that process is a good thing, even better than starting with "Hello world". Why: To write a decent program even for a toy/restricted problem in a new language, you'll have to master many heterogenous concepts (control flow & variables & IO ...), you are tempted to glance over details just to get your program 'to work'. Putting (your understanding of) the facts about the new language in assertions with good descriptions (=success messages) enforces thinking thru/clearness/precision. Grouping topics and adding assertions to such groups is much easier than incorporation features from the 2. chapter of your "Learning X" book to your chapter 1 program. Why not: 'Real' Unit Tests are meant to output "1234 tests ok; 1 failure: saveWorld() chokes on negative input"; 'didactic' Unit Tests should output relevant facts about the new language like perl6 10-string.t # ### p5chop ... ok 13 - p5chop( "cbä" ) returns "ä" ok 14 - after that, victim is changed to "cb" # ### (p6) chop ... ok 27 - (p6) chop( "cbä" ) returns chopped copy: "cb" ok 18 - after that, victim is unchanged: "cbä" # ### chomp ... So (mis?)using Unit Tests may be counterproductive - practicing actions while learning you wouldn't use professionally. How: Writing 'didactic' Unit Tests in languages with lightweight testing systems (Perl 5/6) is easy; (mis?)using more elaborate systems (JUnit, CppUnit) may be not worth the effort or not suitable for a person just starting with a new language. So Is using Unit Tests as a learning tool a bad idea? Can the Unit Test tool(s) of your favourite language(s) used didactically? Should implementation details (eventually) be discussed here or over at stackoverflow.com?

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• Styles of games that work at low-resolution

  - by Brendan Long

  I'm taking a class on compilers, and the goal is to write a compiler for Meggy Jr devices (Arduino). The goal is just to make a simple compilers with loops and variables and stuff. Obviously, that's lame, so the "real goal" is to make an impressive game on the device. The problem is that it only has 64 pixels to work with (technically 72, but the top 8 are single-color and not part of the main display, so they're really only useful for displaying things like money). My problem is thinking of something to do on a device that small. It doesn't really matter if it's original, but it can't be something that's already available. My first idea was "snake", but that comes with the SDK. Same with a side-scrolling shooter. Remaining ideas include a tower defense game (hard to write, hard to control), an RPG (same), tetris (lame).. The problem is that all of the games I like require a high-resolution screen because they have a lot of text. Even a really simple game like nethack would be hard because each creature would be a single color. tl;dr What styles of games require a. No text; and b. Few enough objects that representing them each with a single color is acceptable? EDIT: To clarify, the display is 8x8 for a total of 64 pixels, not 64x64.

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• Styles of games that work at low-resolution

  - by Brendan Long

  I'm taking a class on compilers, and the goal is to write a compiler for Meggy Jr devices (Arduino). The goal is just to make a simple compilers with loops and variables and stuff. Obviously, that's lame, so the "real goal" is to make an impressive game on the device. The problem is that it only has 64 pixels to work with (technically 72, but the top 8 are single-color and not part of the main display, so they're really only useful for displaying things like money). My problem is thinking of something to do on a device that small. It doesn't really matter if it's original, but it can't be something that's already available. My first idea was "snake", but that comes with the SDK. Same with a side-scrolling shooter. Remaining ideas include a tower defense game (hard to write, hard to control), an RPG (same), tetris (lame).. The problem is that all of the games I like require a high-resolution screen because they have a lot of text. Even a really simple game like nethack would be hard because each creature would be a single color. tl;dr What styles of games require a. No text; and b. Few enough objects that representing them each with a single color is acceptable?

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• Could not log-in properly but shows no error in joomla

  - by saeha

  This is what I did, I added variables in \libraries\joomla\database\table\user.php: var $img_content= null; //contains the blob type data var $img_name = null; var $img_type = null; then I added this code in \components\com_user\controller.php: $file = JRequest::getVar( 'pic', '', 'files', 'array' ); if(isset($file['name'])) { jimport('joomla.filesystem.file'); $fileName = $file['name']; $tmpName = $file['tmp_name']; $fileSize = $file['size']; $fileType = $file['type']; $fp = fopen($tmpName, 'r'); $content = fread($fp, filesize($tmpName)); //$content = addslashes($content); fclose($fp); $user->set('img_name', $fileName); $user->set('img_type', $fileType); $user->set('img_content', $content); } that works fine, but I found this problem in logging in with the new user with an uploaded photo, other user with an empty img_content field could login properly. What happens is when I log-in using the user with uploaded photo, it's not redirecting properly it just return to log-in, but when i log-in through backend using other user which is super admin, i could see that user which appears as logged in. I started saving the images in the database because I am having problem with the directory when I have uploaded the site. I think the log-in was affected by the blob type data in the database. Could that be the problem? What could be the solution? -saeha

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• How do you stay productive when dealing with extremely badly written code?

  - by gaearon

  I don't have much experience in working in software industry, being self-taught and having participated in open source before deciding to take a job. Now that I work for money, I also have to deal with some unpleasant stuff, which is normal of course. Recently I was assigned to add logging to a large SharePoint project which is written by some programmer who obviously was learning to code on the job. After 2 years of collaboration, the client switched to our company, but the damage was done, and now somehow I need to maintain this code. Not that the code was too hard to read. Despite problems - each project has one class with several copy-pasted methods, enormous if nestings, Systems Hungarian, undisposed connections — it's still readable. However, I found myself absolutely unproductive despite working on something as simple as adding logging. Basically, I just need to go through the code step by step and add some trace calls. However, the idiocy of the code is so annoying that I get tired within 10 minutes of starting. In the beginning, I used to add using constructs, reduce nesting by reversing if's, rename the variables to readable names—but the project is large, and eventually I gave up. I know this is not the task I should be doing, but at least reducing the mess gave me some kind of psychological reward so I could keep going. Now the trick stopped working, and I still have 60% of my work to do. I started having headaches after work, and I no longer get the feeling of satisfaction I used to get - which would usually allow me to code for 10 hours straight and still feel fresh. This is not just one big rant, for I really do have an actual question: Is there a way to stay productive and not to fight the windmills? Is there some kind of psychological trick to stay focused on the task, instead of thinking “How stupid is that?” each time I see another clever trick by the previous programmer? The problem with adding logging is that I actually have to understand what the code does, and doing so hurts my brain in an unpleasant fashion.

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• correct Installation and configuration of openJDK and R

  - by Marco K

  I am relatively new to Ubuntu so I wont know a lot of commands that probably became standard to a lot of you guys. I am trying to set up R and with it the necessary java dependencies to install e.g. JGR, rjava, etc. I read through quite a few instructions to do that but somehow I must have done sth wrong. Here is the state of R and java: R --version R version 2.14.1 (2011-12-22) Copyright (C) 2011 The R Foundation for Statistical Computing ISBN 3-900051-07-0 Platform: x86_64-pc-linux-gnu (64-bit) java -version java version "1.6.0_23" OpenJDK Runtime Environment (IcedTea6 1.11pre) (6b23~pre11-0ubuntu1.11.10.1) OpenJDK 64-Bit Server VM (build 20.0-b11, mixed mode) R CMD javareconf Java interpreter : /usr/bin/java Java version : 1.6.0_23 Java home path : /usr/lib/jvm/java-6-openjdk/jre Java compiler : /usr/bin/javac Java headers gen.: /usr/bin/javah Java archive tool: /usr/bin/jar Java library path: /usr/lib/jvm/java-6-openjdk/jre/lib/amd64/server:/usr/lib/jvm/java-6-openjdk/jre/lib/amd64:/usr/lib/jvm/java-6-openjdk/jre/../lib/amd64:/usr/java/packages/lib/amd64:/usr/lib/jni:/lib:/usr/lib JNI linker flags : -L/usr/lib/jvm/java-6-openjdk/jre/lib/amd64/server -L/usr/lib/jvm/java-6-openjdk/jre/lib/amd64 -L/usr/lib/jvm/java-6-openjdk/jre/../lib/amd64 -L/usr/java/packages/lib/amd64 -L/usr/lib/jni -L/lib -L/usr/lib -ljvm JNI cpp flags : But when I try to install 'JavaGD' in R, which is a dependency for JGR I get: ... checking Java support in R... present: interpreter : '/usr/bin/java' cpp flags : '' java libs : '-L/usr/lib/jvm/java-6-openjdk/jre/lib/amd64/server -L/usr/lib/jvm/java-6-openjdk/jre/lib/amd64 -L/usr/lib/jvm/java-6-openjdk/jre/../lib/amd64 -L/usr/java/packages/lib/amd64 -L/usr/lib/jni -L/lib -L/usr/lib -ljvm' configure: error: One or more Java configuration variables are not set. Make sure R is configured with full Java support (including JDK). Run R CMD javareconf as root to add Java support to R. ... Any help would be greatly appreciated. Thanks!

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• SQL SERVER – Storing Variable Values in Temporary Array or Temporary List

  - by pinaldave

  SQL Server does not support arrays or a dynamic length storage mechanism like list. Absolutely there are some clever workarounds and few extra-ordinary solutions but everybody can;t come up with such solution. Additionally, sometime the requirements are very simple that doing extraordinary coding is not required. Here is the simple case. Let us say here are the values: a, 10, 20, c, 30, d. Now the requirement is to store them in a array or list. It is very easy to do the same in C# or C. However, there is no quick way to do the same in SQL Server. Every single time when I get such requirement, I create a table variable and store the values in the table variables. Here is the example: For SQL Server 2012: DECLARE @ListofIDs TABLE(IDs VARCHAR(100)); INSERT INTO @ListofIDs VALUES('a'),('10'),('20'),('c'),('30'),('d'); SELECT IDs FROM @ListofIDs; GO When executed above script it will give following resultset. Above script will work in SQL Server 2012 only for SQL Server 2008 and earlier version run following code. DECLARE @ListofIDs TABLE(IDs VARCHAR(100), ID INT IDENTITY(1,1)); INSERT INTO @ListofIDs SELECT 'a' UNION ALL SELECT '10' UNION ALL SELECT '20' UNION ALL SELECT 'c' UNION ALL SELECT '30' UNION ALL SELECT 'd'; SELECT IDs FROM @ListofIDs; GO Now in this case, I have to convert numbers to varchars because I have to store mix datatypes in a single column. Additionally, this quick solution does not give any features of arrays (like inserting values in between as well accessing values using array index). Well, do you ever have to store temporary multiple values in SQL Server – if the count of values are dynamic and datatype is not specified early how will you about storing values which can be used later in the programming. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Source-control your BI Publisher reports

  - by Dmitry Nefedkin

  Version control systems (VCS) like Subversion, Git and the others has been widely adopted and became the must-have tool in any software development project. Source artifacts and checked out, modified, checked in, all the history of changes is tracked by the VCS.  But what if the development tool stores the source/configuration artifacts not in your laptop's hard drive, but in some shared repository instead? Well, we definitely need a way for export/import our artifacts from/to this repository.   Oracle BI Publisher report development approach is based on such a shared repository model (catalog), and starting from BI Publisher 11.1.1.5 Oracle ships Catalog Utility, which can be utilized to export/import the reports from the command line.  To start using the BI Publisher Catalog Utility you should: Go to the file system of the server where BI Publisher binaries has been installed and locate the following file: <MW_HOME>/Oracle_BI1/clients/bipublisher/BIPCatalogUtil.zip Copy the file to your local filesystem and unzip it. I will refer to this unzipped directory as <BIP_CLIENT_DIR> below If you do not want to pass server BI Publisher server URL, username and password during each invocation, modify the corresponding values inside <BIP_CLIENT_DIR>/config/xmlp-client-config.xml Open the terminal window and go to <BIP_CLIENT_DIR>/bin Make sure that the following environment variables are set: JAVA_HOME, ORACLE_HOME Now it's time to run the utility: if you are on Linux - just run BIPCatalogUtil.sh and pass the parameters according to the utility documentation if you are on MS Windows the bad news are that the command script for MS Windows is missing, and support.oracle.com note 1333726.1 says that a temporary solution is "create a .cmd file by setting up a classpath and copying the same commands from the .sh script". The good news are that I've created this script already,  please download the it from GitHub Hope you will find this utility useful during you day-by-day BI Publisher development. 

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• Bulk Rename Tool is a Lightweight but Powerful File Renaming Tool

  - by Jason Fitzpatrick

  There’s no need to settle for overly simplistic file renaming tools as long as Bulk Rename Tool is around. It’s lightweight, insanely customizable, portable, and sure to make short work of any renaming task you throw at it. Bulk Rename Tool is a great portable application (available as an installed version if you crave context menu integration) that blasts through file renaming tasks. The main panel is intimidatingly packed with toggles and variables you can alter; this isn’t a one-click solution by any means. That said, once you get comfortable using the interface it’s lightening fast and extremely flexible. One tip that will save you an enormous amount of frustrating when you get started: make sure to highlight the files you want to change in the file preview window (located in the upper right corner) or else you won’t see the preview and won’t know if the changes you’re making in the control panel are yielding the file names you desire. Hit up the link below to read more and grab a copy; Bulk Rename Tool is free, Windows only. Bulk Rename Tool Latest Features How-To Geek ETC How To Make Disposable Sleeves for Your In-Ear Monitors Macs Don’t Make You Creative! So Why Do Artists Really Love Apple? MacX DVD Ripper Pro is Free for How-To Geek Readers (Time Limited!) HTG Explains: What’s a Solid State Drive and What Do I Need to Know? How to Get Amazing Color from Photos in Photoshop, GIMP, and Paint.NET Learn To Adjust Contrast Like a Pro in Photoshop, GIMP, and Paint.NET Bring the Grid to Your Desktop with the TRON Legacy Theme for Windows 7 The Dark Knight and Team Fortress 2 Mashup Movie Trailer [Video] Dirt Cheap DSLR Viewfinder Improves Outdoor DSLR LCD Visibility Lakeside Sunset in the Mountains [Wallpaper] Taskbar Meters Turn Your Taskbar into a System Resource Monitor Create Shortcuts for Your Favorite or Most Used Folders in Ubuntu

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• ORA-600 Troubleshooting

  - by [email protected]

  Have you observed an ORA-0600 or ORA-07445 reported in your alert log? The ORA-600 error is the generic internal error number for Oracle program exceptions. It indicates that a process has encountered a low-level, unexpected condition. The ORA-600 error statement includes a list of arguments in square brackets: ORA 600 "internal error code, arguments: [%s], [%s],[%s], [%s], [%s]" The first argument is the internal message number or character string. This argument and the database version number are critical in identifying the root cause and the potential impact to your system.  The remaining arguments in the ORA-600 error text are used to supply further information (e.g. values of internal variables etc).   Looking for the best way to diagnose? There is an ORA-600 Troubleshooter Tool available in My Oracle Support.  This tool will lead you to applicable content in My Oracle Support on the problem and can be used to investigate the problem with argument data from the error message or you can pull out the first 10 or 15 stack pointers from the associated trace file to match up against known bugs. Note 153788.1 ORA-600/ORA-7445 TroubleshooterNote 1082674.1 A Video To Demonstrate The Usage Of The ORA-600/ORA-7445 Lookup Tool [Video] Also, take a quick look at the Master Note for Diagnosing ORA-600 ( MasterNoteORA600.docx) for some tips on diagnosing.

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• Why unhandled exceptions are useful

  - by Simon Cooper

  It’s the bane of most programmers’ lives – an unhandled exception causes your application or webapp to crash, an ugly dialog gets displayed to the user, and they come complaining to you. Then, somehow, you need to figure out what went wrong. Hopefully, you’ve got a log file, or some other way of reporting unhandled exceptions (obligatory employer plug: SmartAssembly reports an application’s unhandled exceptions straight to you, along with the entire state of the stack and variables at that point). If not, you have to try and replicate it yourself, or do some psychic debugging to try and figure out what’s wrong. However, it’s good that the program crashed. Or, more precisely, it is correct behaviour. An unhandled exception in your application means that, somewhere in your code, there is an assumption that you made that is actually invalid. Coding assumptions Let me explain a bit more. Every method, every line of code you write, depends on implicit assumptions that you have made. Take this following simple method, that copies a collection to an array and includes an item if it isn’t in the collection already, using a supplied IEqualityComparer: public static T[] ToArrayWithItem( ICollection<T> coll, T obj, IEqualityComparer<T> comparer) { // check if the object is in collection already // using the supplied comparer foreach (var item in coll) { if (comparer.Equals(item, obj)) { // it's in the collection already // simply copy the collection to an array // and return it T[] array = new T[coll.Count]; coll.CopyTo(array, 0); return array; } } // not in the collection // copy coll to an array, and add obj to it // then return it T[] array = new T[coll.Count+1]; coll.CopyTo(array, 0); array[array.Length-1] = obj; return array; } What’s all the assumptions made by this fairly simple bit of code? coll is never null comparer is never null coll.CopyTo(array, 0) will copy all the items in the collection into the array, in the order defined for the collection, starting at the first item in the array. The enumerator for coll returns all the items in the collection, in the order defined for the collection comparer.Equals returns true if the items are equal (for whatever definition of ‘equal’ the comparer uses), false otherwise comparer.Equals, coll.CopyTo, and the coll enumerator will never throw an exception or hang for any possible input and any possible values of T coll will have less than 4 billion items in it (this is a built-in limit of the CLR) array won’t be more than 2GB, both on 32 and 64-bit systems, for any possible values of T (again, a limit of the CLR) There are no threads that will modify coll while this method is running and, more esoterically: The C# compiler will compile this code to IL according to the C# specification The CLR and JIT compiler will produce machine code to execute the IL on the user’s computer The computer will execute the machine code correctly That’s a lot of assumptions. Now, it could be that all these assumptions are valid for the situations this method is called. But if this does crash out with an exception, or crash later on, then that shows one of the assumptions has been invalidated somehow. An unhandled exception shows that your code is running in a situation which you did not anticipate, and there is something about how your code runs that you do not understand. Debugging the problem is the process of learning more about the new situation and how your code interacts with it. When you understand the problem, the solution is (usually) obvious. The solution may be a one-line fix, the rewrite of a method or class, or a large-scale refactoring of the codebase, but whatever it is, the fix for the crash will incorporate the new information you’ve gained about your own code, along with the modified assumptions. When code is running with an assumption or invariant it depended on broken, then the result is ‘undefined behaviour’. Anything can happen, up to and including formatting the entire disk or making the user’s computer sentient and start doing a good impression of Skynet. You might think that those can’t happen, but at Halting problem levels of generality, as soon as an assumption the code depended on is broken, the program can do anything. That is why it’s important to fail-fast and stop the program as soon as an invariant is broken, to minimise the damage that is done. What does this mean in practice? To start with, document and check your assumptions. As with most things, there is a level of judgement required. How you check and document your assumptions depends on how the code is used (that’s some more assumptions you’ve made), how likely it is a method will be passed invalid arguments or called in an invalid state, how likely it is the assumptions will be broken, how expensive it is to check the assumptions, and how bad things are likely to get if the assumptions are broken. Now, some assumptions you can assume unless proven otherwise. You can safely assume the C# compiler, CLR, and computer all run the method correctly, unless you have evidence of a compiler, CLR or processor bug. You can also assume that interface implementations work the way you expect them to; implementing an interface is more than simply declaring methods with certain signatures in your type. The behaviour of those methods, and how they work, is part of the interface contract as well. For example, for members of a public API, it is very important to document your assumptions and check your state before running the bulk of the method, throwing ArgumentException, ArgumentNullException, InvalidOperationException, or another exception type as appropriate if the input or state is wrong. For internal and private methods, it is less important. If a private method expects collection items in a certain order, then you don’t necessarily need to explicitly check it in code, but you can add comments or documentation specifying what state you expect the collection to be in at a certain point. That way, anyone debugging your code can immediately see what’s wrong if this does ever become an issue. You can also use DEBUG preprocessor blocks and Debug.Assert to document and check your assumptions without incurring a performance hit in release builds. On my coding soapbox… A few pet peeves of mine around assumptions. Firstly, catch-all try blocks: try { ... } catch { } A catch-all hides exceptions generated by broken assumptions, and lets the program carry on in an unknown state. Later, an exception is likely to be generated due to further broken assumptions due to the unknown state, causing difficulties when debugging as the catch-all has hidden the original problem. It’s much better to let the program crash straight away, so you know where the problem is. You should only use a catch-all if you are sure that any exception generated in the try block is safe to ignore. That’s a pretty big ask! Secondly, using as when you should be casting. Doing this: (obj as IFoo).Method(); or this: IFoo foo = obj as IFoo; ... foo.Method(); when you should be doing this: ((IFoo)obj).Method(); or this: IFoo foo = (IFoo)obj; ... foo.Method(); There’s an assumption here that obj will always implement IFoo. If it doesn’t, then by using as instead of a cast you’ve turned an obvious InvalidCastException at the point of the cast that will probably tell you what type obj actually is, into a non-obvious NullReferenceException at some later point that gives you no information at all. If you believe obj is always an IFoo, then say so in code! Let it fail-fast if not, then it’s far easier to figure out what’s wrong. Thirdly, document your assumptions. If an algorithm depends on a non-trivial relationship between several objects or variables, then say so. A single-line comment will do. Don’t leave it up to whoever’s debugging your code after you to figure it out. Conclusion It’s better to crash out and fail-fast when an assumption is broken. If it doesn’t, then there’s likely to be further crashes along the way that hide the original problem. Or, even worse, your program will be running in an undefined state, where anything can happen. Unhandled exceptions aren’t good per-se, but they give you some very useful information about your code that you didn’t know before. And that can only be a good thing.

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