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• Good book about advanced programming techniques [closed]

  - by Luca

  I am looking to a book covering adavnced programming techniques, covering different practical scenarios and describing the different challanges with the relative solutions. As example, which are the best ways to implement a module for buying on a web application with credit card or how to manage responsivenes for the frontend of the web application itself (dealing with cache, optimeze plugins, etc). On the web there are tons of tutorials about these topics, but I am looking for a book where such cases are collected all together and treated by real professionists. If the book would provide some code samples, that would be a plus (especially if C# .NET), but I am more interested in the approach/solution rather than the code details. I could not find any of these cases in the general book about programming, therefore I hope someone might point me in the right direction. EDIT: I have 4 years experience as web developer, mainly with Microsoft (C#, ASP.NET, SQL Server) and client side technologies (jQuery, HTML/CSS).

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• How do i get out of the habit of procedural programming and into object oriented programming?

  - by Shadi Almosri

  Hiya all, I'm hoping to get some tips to kinda help me break out of what i consider after all these years a bad habit of procedural programming. Every time i attempt to do a project in OOP i end up eventually reverting to procedural. I guess i'm not completely convinced with OOP (even though i think i've heard everything good about it!). So i guess any good practical examples of common programming tasks that i often carry out such as user authentication/management, data parsing, CMS/Blogging/eComs are the kinda of things i do often, yet i haven't been able to get my head around how to do them in OOP and away from procedural, especially as the systems i build tend to work and work well. One thing i can see as a downfall to my development, is that i do reuse my code often, and it often needs more rewrites and improvement, but i sometimes consider this as a natural evolution of my software development. Yet i want to change! to my fellow programmers, help :) any tips on how i can break out of this nasty habbit?

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• Setting unique key constraint for Db4oEmbedded EmbeddedConfiguration

  - by Viet

  Hi, I want to set unique key constraint for Db4oEmbedded EmbeddedConfiguration. Here goes my code: EmbeddedConfiguration myConf = Db4oEmbedded.newConfiguration(); myConf.common().objectClass(NotyUser.class).objectField("username").indexed(true); myConf.common().add(new com.db4o.constraints.UniqueFieldValueConstraint(NotyUser.class, "username")); The last line throws exception. I don't know why. I'm running Android SDK 1.5 and db4o 7.12 for Java. Please kindly advise. Thanks!

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• Catching constraint violations in JPA 2.0.

  - by Dennetik

  Consider the following entity class, used with, for example, EclipseLink 2.0.2 - where the link attribute is not the primary key, but unique nontheless. @Entity public class Profile { @Id private Long id; @Column(unique = true) private String link; // Some more attributes and getter and setter methods } When I insert records with a duplicate value for the link attribute, EclipseLink does not throw a EntityExistsException, but throws a DatabaseException, with the message explaining that the unique constraint was violated. This doesn't seem very usefull, as there would not be a simple, database independent, way to catch this exception. What would be the advised way to deal with this? A few things that I have considered are: Checking the error code on the DatabaseException - I fear that this error code, though, is the native error code for the database; Checking the existence of a Profile with the specific value for link beforehand - this obviously would result in an enormous amount of superfluous queries.

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• PHP MySQL INSERT fails due to unique constraint

  - by sjw

  On insert I am catching the unique constraint mysql_errno() 1062. This works fine but I want to find the existing row to re-instate or modify it. Is there are method to obtain the row id on insert fail? I tried mysql_insert_id() but realised that would only return the row I'm inserting (or failed to insert) therefore, I get 0. Is there no option but to issue another mysql_query and simply perform a select on the duplicate value? I just want to make sure there is no better, quicker, more economical way to do this.

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• SQL Server 2005: When copy table structure to other database "CONSTRAINT" keywords lost

  - by StreamT

  Snippet of original table: CREATE TABLE [dbo].[Batch]( [CustomerDepositMade] [money] NOT NULL CONSTRAINT [DF_Batch_CustomerDepositMade] DEFAULT (0) Snippet of copied table: CREATE TABLE [dbo].[Batch]( [CustomerDepositMade] [money] NOT NULL, Code for copy database: Server server = new Server(SourceSQLServer); Database database = server.Databases[SourceDatabase]; Transfer transfer = new Transfer(database); transfer.CopyAllObjects = true; transfer.CopySchema = true; transfer.CopyData = false; transfer.DropDestinationObjectsFirst = true; transfer.DestinationServer = DestinationSQLServer; transfer.CreateTargetDatabase = true; Database ddatabase = new Database(server, DestinationDatabase); ddatabase.Create(); transfer.DestinationDatabase = DestinationDatabase; transfer.Options.IncludeIfNotExists = true; transfer.TransferData();

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• Unique constraint not created in JPA

  - by homaxto

  I have created the following entity bean, and specified two columns as being unique. Now my problem is that the table is created without the unique constraint, and no errors in the log. Does anyone have an idea? @Entity @Table(name = "cm_blockList", uniqueConstraints = @UniqueConstraint(columnNames = {"terminal", "blockType"})) public class BlockList { @Id @GeneratedValue(strategy = GenerationType.AUTO) private int id; @ManyToOne(cascade = CascadeType.PERSIST) @JoinColumn(name="terminal") private Terminal terminal; @Enumerated(EnumType.STRING) private BlockType blockType; private String regEx; }

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• Unique constraint on more than 10 columns

  - by tk

  I have a time-series simulation model which has more than 10 input variables. The number of distinct simulation instances would be more than 1 million, and each simulation instance generates a few output rows every day. To save the simulation result in a relational database, i designed tables like this. Table SimulationModel { simul_id : integer (primary key), input0 : string or numeric, input1 : string or numeric, ...} Table SimulationOutput { dt : DateTime (primary key), simul_id : integer (primary key), output0 : numeric, ...} My question is, is it fine to put an unique constraint on all of the input columns of SimulationModel table? If it is not a good idea, then what kind of other options do i have to make sure each model is unique?

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• Mutating Programming Language?

  - by MattiasK

  For fun I was thinking about how one could build a programming language that differs from OOP and came up with this concept. I don't have a strong foundation in computer science so it might be common place without me knowing it (more likely it's just a stupid idea :) I apologize in advance for this somewhat rambling question :) Anyways here goes: In normal OOP methods and classes are variant only upon parameters, meaning if two different classes/methods call the same method they get the same output. My, perhaps crazy idea, is that the calling method and class could be an "invisible" part of it's signature and the response could vary depending on who call's an method. Say that we have a Window object with a Break() method, now anyone (who has access) could call this method on Window with the same result. Now say that we have two different objects, Hammer and SledgeHammer. If Break need to produce different results based on these we'd pass them as parameters Break(IBluntObject bluntObject) With a mutating programming language (mpl) the operating objects on the method would be visible to the Break Method without begin explicitly defined and it could adopt itself based on them). So if SledgeHammer calls Window.Break() it would generate vastly different results than if Hammer did so. If OOP classes are black boxes then MPL are black boxes that knows who's (trying) to push it's buttons and can adapt accordingly. You could also have different permission sets on methods depending who's calling them rather than having absolute permissions like public and private. Does this have any advantage over OOP? Or perhaps I should say, would it add anything to it since you should be able to simply add this aspect to methods (just give access to a CallingMethod and CallingClass variable in context) I'm not sure, might be to hard to wrap one's head around, it would be kinda interesting to have classes that adopted themselves to who uses them though. Still it's an interesting concept, what do you think, is it viable?

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• How do I create my own programming language and a compiler for it

  - by Dave

  I am thorough with programming and have come across languages including BASIC, FORTRAN, COBOL, LISP, LOGO, Java, C++, C, MATLAB, Mathematica, Python, Ruby, Perl, JavaScript, Assembly and so on. I can't understand how people create programming languages and devise compilers for it. I also couldn't understand how people create OS like Windows, Mac, UNIX, DOS and so on. The other thing that is mysterious to me is how people create libraries like OpenGL, OpenCL, OpenCV, Cocoa, MFC and so on. The last thing I am unable to figure out is how scientists devise an assembly language and an assembler for a microprocessor. I would really like to learn all of these stuff and I am 15 years old. I always wanted to be a computer scientist someone like Babbage, Turing, Shannon, or Dennis Ritchie. I have already read Aho's Compiler Design and Tanenbaum's OS concepts book and they all only discuss concepts and code in a high level. They don't go into the details and nuances and how to devise a compiler or operating system. I want a concrete understanding so that I can create one myself and not just an understanding of what a thread, semaphore, process, or parsing is. I asked my brother about all this. He is a SB student in EECS at MIT and hasn't got a clue of how to actually create all these stuff in the real world. All he knows is just an understanding of Compiler Design and OS concepts like the ones that you guys have mentioned (i.e. like Thread, Synchronization, Concurrency, memory management, Lexical Analysis, Intermediate code generation and so on)

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• How to diagram custom programming languages, non textual?

  - by Adam

  I've used and created domain-specific languages before, plenty of times (e.g. using yacc/lex). Normally we'd start with grammar written in BNF, and a bunch of keywords. This is easy to do, easy to share. Recently, I've started working with diagrammatic programming languages - closest parallel is circuit-diagrams in electronics, where it's very difficult to express ideas in text, but very easy to express them in wiring-diagrams. This is a new and novel problem for me: how to efficiently express these mini-languages, and share concepts in them with colleagues? (i.e. how to whiteboard-program within them. Actual programming is easy - you have physical components to hand) Are there tools for this? Or good/best practices (e.g. equivalent of "always use BNF as starting point for your new DSL, and use tools like yacc to generate the parser, compiler, etc"). My googlefu is proving weak - all I get is false positives for wiring diagrams, and UML editors (since these are custom languages, UML doesn't seem to help)

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• How do I create my own programming language and a compiler for it

  - by Dave

  I am thorough with programming and have come across languages including BASIC, FORTRAN, COBOL, LISP, LOGO, Java, C++, C, MATLAB, Mathematica, Python, Ruby, Perl, Javascript, Assembly and so on. I can't understand how people create programming languages and devise compilers for it. I also couldn't understand how people create OS like Windows, Mac, UNIX, DOS and so on. The other thing that is mysterious to me is how people create libraries like OpenGL, OpenCL, OpenCV, Cocoa, MFC and so on. The last thing I am unable to figure out is how scientists devise an assembly language and an assembler for a microprocessor. I would really like to learn all of these stuff and I am 15 years old. I always wanted to be a computer scientist some one like Babbage, Turing, Shannon, or Dennis Ritchie. I have already read Aho's Compiler Design and Tanenbaum's OS concepts book and they all only discuss concepts and code in a high level. They don't go into the details and nuances and how to devise a compiler or operating system. I want a concrete understanding so that I can create one myself and not just an understanding of what a thread, semaphore, process, or parsing is. I asked my brother about all this. He is a SB student in EECS at MIT and hasn't got a clue of how to actually create all these stuff in the real world. All he knows is just an understanding of Compiler Design and OS concepts like the ones that you guys have mentioned (ie like Thread, Synchronisation, Concurrency, memory management, Lexical Analysis, Intermediate code generation and so on)

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• My Only Gripe With Programming

  - by David Espejo

  Is that im having trouble practicing problems. Even if I decide to practice the problems from my C++ book, they dont give any idea of the way the solution(program) should look like, so that I may compare to see if my program is similar in anyway. My book gives me to many generic "Write a program to do "this" " projects without really showing a concrete example of what "this" really is. In other words How Do I Know That I did "that". One problem in my book said to write a program that calculates the sales tax on a given item????? First of all slase tax differs on state(whats the state,) whats the item(a house, a dog,) How can I check this to see if im right. Programming books dont have answer keys! I know that there is no ABSOLUTE answer, thats just silly, programs can be written in many ways, but a sample of what one would look like based of the difficulty of the problem would really help! Is there a solution to this, maby a book that has worked out examples for the problems they give , or online sources that do something similar.(is there such thing as a programming book with an answer key?)

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• What constitutes a programming language and how does one copyright a programming language?

  - by Yannbane

  I've decided to create a programming language of my own, mostly just for fun. However, I got interested in the legal aspect of it all. You can, for example, licence specific programs under specific terms. However, how do you go about licensing a language? Also, by that I don't just mean the implementation of the language (compiler & VM), but the standard itself. Is there something else to a programming language I'm missing? What I would like to achieve by such licensing: Make it completely FOSS (can a language even be FOSS, or is that the implementation that can be FOSS?) Establish myself as the author (can you legally be an author of a language? Or, again, just the implementation?) Make it so that anyone implementing my language would be required to attribute me (MIT-style. Please note that I do not have any hopes for anyone actually ever doing that though, I'm just learning.) I think that the solution would be to separately license the VM and the compiler for my language, as "the official implementation", and then license the design document as the language itself. What exactly am I missing here?

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• Getting into the details of game engine programming

  - by Darkslash

  I am interested in learning game programming, but I really have an interest in the lower level engineering in games. I have OpenGL experience, and I am really interested in learning more about implementing AI, Physics, etc. I have a computer science degree, so I really like getting into technical stuff. Many times when I ask about this sort of thing, I get a lot of "Use an engine", "Use Unity3d", "Why waste your time writing code that already exists", etc, etc. My idea was to use simpler libraries such as SFML or XNA so that I could learn how to implement the more complex systems. The thing is, although I do want to write games, I want to learn things that using something like Unity simply doesn't teach you. My goal is not to make a current generation quality 3D game to sell, I just want to make some cool smaller games and learn all I can about the programming side of game development. Is this something that people just do not do anymore? It seems like everywhere I turn people are using Unity or UDK or GameMaker. I fully understand why you would use a tool like these, but I cant see how they would suit my purposes. So where does someone like myself turn? Am I trying to learn something that people just do not bother doing anymore? Is the innovation in this area gone and just all about gameplay now? I'm sorry if this question seems silly, but I am genuinely interested in knowing more about this and meeting more people who are interested in this sort of thing.

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• Programming in python Vs programming in Java

  - by yossale

  I've been writing Java for the last couple of years , and now I've started to write in python (in addition). The problem is that when I look at my Python code it looks like someone tried to hammer Java code into a python format , and it comes out crappy because - well , python ain't Java. Any tips on how to escape this pattern of "Writing Java in Python"? Thanks!

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• Programming activities for high school kids who have no idea what CS or programming is

  - by pointdxt

  I work at a small high school that's in a very high poverty area. There are only a handful of seniors that are thinking about applying to be an engineer of some sort in college and only 1 kid that applied for Computer Science (he has a couple acceptances so far!). He's been talking to me a lot as I majored in Computer Science as well and he is very excited about it. Unfortunately, our school doesn't have a Computer Science course of any kind so he asks me a lot of stuff. I want to help him out since he's really excited about majoring in CS but I don't know where to begin. I could say put Linux on a computer, go online and go research stuff like I did but this kid needs some direction and he doesn't even know what Linux is let alone have a free computer around for that sort of thing. He doesn't know much about CS but is keenly interested in having a computer do all sorts of things but I don't know how to help him in a meaningful way. Any advice? I'm not a teacher at the school so I'm not a great educator, I do IT at the school.

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• The future of programming, or what lies in the future in programming?

  - by prosseek

  I remember that a article that Microsoft uses formal verification to debug the Device Driver, and I also remember that Functional Programming removes much of the bug as it ensures stateless programming. And we all know about the multi-core. I beleive all of them are future direction of programming or programming language. Multi-core programming or parallel programming Software Formal Verification Functional Programming (as a mainstream?) What do you think? What will be the future of programming?

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• Which order would you teach programming languages in, when teaching a newbie?

  - by blueberryfields

  If you had to design a study program, with a breadth-of-programming-languages requirement, which stated that the student should be exposed to all major concepts and methodologies that can be taught through (at the minimum) 6 programming languages, which programming languages would you choose to teach, and in which order? Breadth-of-programming-languages is based on programming language and theoretical concepts.

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• Solutions to the 'Programming Pearls' book by Jon Bentley

  - by coder

  Hi.. Is there a place where I can find the solutions to the 'Programming Pearls' book by Jon Bentley ? I need to verify what ever little exercise problems I solve.. Thank you ..

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• Good practices - database programming, unit testing

  - by Piotr Rodak

  Jason Brimhal wrote today on his blog that new book, Defensive Database Programming , written by Alex Kuznetsov ( blog ) is coming to bookstores. Alex writes about various techniques that make your code safer to run. SQL injection is not the only one vulnerability the code may be exposed to. Some other include inconsistent search patterns, unsupported character sets, locale settings, issues that may occur during high concurrency conditions, logic that breaks when certain conditions are not met. The...(read more)

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• Datatype-generic programming libraries for Scala

  - by kohomologie

  I'm looking for a Scala library allowing for datatype-generic programming (like Scrap Your Boilerplate, for example). A list of libraries with appropriate links and short descriptions for each one would be a perfect answer.

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• Best Programming Language for Web Development

  - by Harish Kurup

  I am a Web Developer in PHP, and also know Javascript and some bit of CSS which is needed for web development. I use Symfony framework to build Websites and Web Application. As now i want to learn new Programming Language, which is best for Web Development(like Ruby, Python), as i have heard about Frameworks like Rails and Django. Which language will be best for Web Development apart from PHP or like PHP?

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• Does syntax really matter in a programming language?

  - by Saif al Harthi

  One of my professors says "the Syntax is the UI of a programming language", languages like ruby have great readability & its growing but we see alot of programmers productive with C\C++, so as programmers does it really matter that the syntax should be acceptable? I would love to know your opinion on that. Disclaimer: I'm not trying to start an argument I thought this is a good topic of discussion. Update : this turns out to be a good topic i'm glad you are all participating it , there will be more good questions to come

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• Dealing with state problems in functional programming

  - by Andrew Martin

  I've learned how to program primarily from an OOP standpoint (like most of us, I'm sure), but I've spent a lot of time trying to learn how to solve problems the functional way. I have a good grasp on how to solve calculational problems with FP, but when it comes to more complicated problems I always find myself reverting to needing mutable objects. For example, if I'm writing a particle simulator, I will want particle "objects" with a mutable position to update. How are inherently "stateful" problems typically solved using functional programming techniques?

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