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  • Java performance of StringBuilder append chains

    - by ultimate_guy
    In Java, if I am building a significant number of strings, is there any difference in performance in the following two examples? StringBuilder sb = new StringBuilder(); for (int i = 0; i < largeNumber; i++) { sb.append(var[i]); sb.append('='); sb.append(value[i]); sb.append(','); } or StringBuilder sb = new StringBuilder(); for (int i = 0; i < largeNumber; i++) { sb.append(var[i]).append('=').append(value[i]).append(','); } Thanks!

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  • A good software development book [closed]

    - by Mahmoud Hossam
    I've searched this website, as well as SO for a question like that, and I still haven't found what I'm looking for. I'm looking for a book that is similar to Head First Software Development. I want to know more about the different stages of software development, I know about coding already, but I don't know much about unit testing, version control, integration, design...etc. P.S. it'd be nice if the book wasn't a thousand pages long. Edit: I'm looking for an introductory text, not a book about the latest trends in software development.

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  • I need help on methodologies for information system project [closed]

    - by Neenee Kale
    Basically I will be developing a student information system for parents and I am confused on what type of methodology I can use. Please recommend me a methodology which involves use cases the system development life cycle. I'm confused on what a methodology is as I've read loads of books and researched but I still don't seem to understand. I was going to use system development life cycle but I found out that this is not a methodology.

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  • Fastest Functional Language

    - by Farouk
    I've recently been delving into functional programming especially Haskell and F#, the prior more so. After some googling around I could not find a benchmark comparison of the more prominent functional languages (Scala,F# etc). I know it's not necessarily fair to some of the languages (Scala comes to mind) given that they are hybrids, but I just wanna know which outperforms which on what operations and overall.

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  • Is it bad to join open-source projects as an amateur?

    - by esqew
    I've thought for about six months now that I should join an open-source iPhone or iPad project to hone my skills in Objective-C, but every time I go to do it I see thousands of lines of code on huge projects that I end up convincing myself I would never understand. I always think that my commits would just end up being a hassle for project admins and more senior contributors, so I always back out at the last second. My question essentially is, is it a hassle when an intermediately-experienced programmer joins an open-source project?

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  • Is there a way communicate or measure levels of abstraction?

    - by hydroparadise
    I'll be the first to say that this question is a bit... out there. But here are a couple questions I bear in mind : Is abstraction continuous or discrete? Is there a single unit of abstraction? But I'm not sure those questions are truly answerable or even really makes sence. My naive answer would be something along the lines of abitrarily discrete but not necescarily having a single unit measure. Here's what I mean... Take a Black Labrador; an abstraction that could be made is that a Black Lab is a type of animal. [Animal]<--[Black Lab] A Black Lab is also a type of Dog. [Dog]<--[Black Lab] One way to establish a degree of abstraction is by comparing the two the abstractions. We could say that [Animal] is more abstract than [Dog] in respect to a Black Lab. It just so happens [Animal] can also be used as an abstraction of [Dog] So, we might end up with something like [Animal]<--[Dog]<--[Black Lab] With the model above, one might be inclined to say that there's two hops of abstraction to get from [Black Lab] to [Animal]. But you can't exactly tell somebody they need one level abstraction and reasonalby expect they will come up with [Dog] given they aren't explicity given the options above. If I needed to tell someobody in a single email that they needed an abstract class with out knowing what that abstract class is, is there a way to communaticate a degree of abstraction such that they might end up on Dog instead of Animal? As a side note, what area of study might this type of analysis fall under?

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  • Understanding the static keyword

    - by user985482
    I have some experience in developing with Java, Javascript and PHP. I am reading Microsoft Visual C# 2010 Step by Step which I feel it is a very good book on introducing you to the C# language. I seem to be having problems in understanding the static keyword. From what I understand this far if a class is declared static all methods and variable have to be static. The main method always is a static method so in the class that the main method exists all variables and methods are declared static if you have to call them in the main method. Also I have noticed that in order to call a static method from another class you do not need to create an object of that you can use the class name. What are the advantages of declaring static variables and methods? When should I declare static variable and methods?

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  • MPL 1.1 and APL 2.0 License compatibility

    - by Kenneth Cochran
    I am working a project that is licensed under the MPL 1.1 and would like to incorporate some code that is licensed under the APL 2.0. I know in 2010 Mozilla announced they were updating the MPL to make it more "Apache compatible" among other things. I'm no lawyer. Exactly what part(s) of the MPL 1.1 don't jive with the APL 2.0 and vice versa? The project has very few of its original contributers still actively involved so I doubt I'd be able to contact all of them to get permission to change the license.

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  • "Integratable" but not "integrated" GPL

    - by mgibsonbr
    There has been much debate over whether or not merely linking to a piece of code makes it a derivative work. I know FSF says "yes", so according to them I can't dynamically link a non-GPL compatible program to a GPL library and distribute the whole. But I could do that for private use, as long as no code is released to the public. That made me wonder: what if I don't redistribute the GPL code at all? If my program can work alone (reinforcing my claim that it's not a derivative work), but can do more if the GPL library is also installed to the system, couldn't I just release my application under my own licensing terms - without including any GPL code - and post instructions for anyone interested to separately download the GPL code and do the integration "for their private use"? I know it's against the "spirit" of the GPL, so I'm not suggesting it's a good idea to do that. However, this question is bugging me for some time, specially because of the implications of each answer: If I can not do that: can I write another library with a similar API? (before answering "of course you can", remember that having the same API would allow both libraries to be swapped at will by my customers - so I don't need to work too hard on my library or even make it "working". How to determine if a similar program is just similar or is a circumvention attempt?) If I can do that: can I also be paid to perform the service of installing the GPL library for a customer? (I sell them my program, install it in their machines, download and install the GPL library too) can I put the two programs in the same website? In two different CDs? (I know I said the idea was not to redistribute the GPL code, I'm just thinking in excuses people could use to claim they're not redistributing even though they are)

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  • Central Exception Handler

    - by J-unior
    Recently I've been thinking about a general ExceptionHandler, that I could initialize once in my app context and inject it everywhere. The idea that it will have quite simple interface with just public void handle(Exception ex), and then according to exception type it should decide what to do, maybe just log it, or show an alert message to the user, or maybe kill the whole app. The question is, what is the prettiest way to write such handler without lots of instanceofs? Unfortunately googling gives me only the default exception handler for RuntimeException that was introduced in Java 5. My first idea is to create an enum, that will have Class field for exception type and it will return the appropriate execution point, for example a concrete exception handler that also implements the interface public void handle(Exception ex), but with the required casting already.

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  • Is there an alternative to Google Code Search?

    - by blunders
    Per the Official Google Blog: Code Search, which was designed to help people search for open source code all over the web, will be shut down along with the Code Search API on January 15, 2012. Google Code Search is now gone, and since that makes it much harder to understand the features it presented, here's my attempt to render them via information I gathered from a cache of the page for the Search Options: The "In Search Box" just notes the syntax to type the command directly in the main search box instead of using the advance search interface. Package (In Search Box: "package:linux-2.6") Language (In Search Box: "lang:c++") (OPTIONS: any language, actionscript, ada, applescript, asp, assembly, autoconf, automake, awk, basic, bat, c, c#, c++, caja, cobol, coldfusion, configure, css, d, eiffel, erlang, fortran, go, haskell, inform, java, java, javascript, jsp, lex, limbo, lisp, lolcode, lua, m4, makefile, maple, mathematica, matlab, messagecatalog, modula2, modula3, objectivec, ocaml, pascal, perl, php, pod, prolog, proto, python, python, r, rebol, ruby, sas, scheme, scilab, sgml, shell, smalltalk, sml, sql, svg, tcl, tex, texinfo, troff, verilog, vhdl, vim, xslt, xul, yacc) File (In Search Box: "file:^.*.java$") Class (In Search Box: "class:HashMap") Function (In Search Box: "function:toString") License (In Search Box: "license:mozilla") (OPTIONS: null/any-license, aladdin/Aladdin-Public-License, artistic/Artistic-License, apache/Apache-License, apple/Apple-Public-Source-License, bsd/BSD-License, cpl/Common-Public-License, epl/Eclipse-Public-License, agpl/GNU-Affero-General-Public-License, gpl/GNU-General-Public-License, lgpl/GNU-Lesser-General-Public-License, disclaimer/Historical-Permission-Notice-and-Disclaimer, ibm/IBM-Public-License, lucent/Lucent-Public-License, mit/MIT-License, mozilla/Mozilla-Public-License, nasa/NASA-Open-Source-Agreement, python/Python-Software-Foundation-License, qpl/Q-Public-License, sleepycat/Sleepycat-License, zope/Zope-Public-License) Case Sensitive (In Search Box: "case:no") (OPTIONS: yes, no) Also of use in understanding the search tool would be the still live FAQs page for Google Code Search. Is there any code search engine that would fully replace Google Code Search's features?

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  • Handling Coding Standards at Work (I'm not the boss)

    - by Josh Johnson
    I work on a small team, around 10 devs. We have no coding standards at all. There are certain things that have become the norm but some ways of doing things are completely disparate. My big one is indentation. Some use tabs, some use spaces, some use a different number of spaces, which creates a huge problem. I often end up with conflicts when I merge because someone used their IDE to auto format and they use a different character to indent than I do. I don't care which we use I just want us all to use the same one. Or else I'll open a file and some lines have curly brackets on the same line as the condition while others have them on the next line. Again, I don't mind which one so long as they are all the same. I've brought up the issue of standards to my direct manager, one on one and in group meetings, and he is not overly concerned about it (there are several others who share the same view as myself). I brought up my specific concern about indentation characters and he thought a better solution would be to, "create some kind of script that could convert all that when we push/pull from the repo." I suspect that he doesn't want to change and this solution seems overly complicated and prone to maintenance issues down the road (also, this addresses only one manifestation of a larger issue). Have any of you run into a similar situation at work? If so, how did you handle it? What would be some good points to help sell my boss on standards? Would starting a grass roots movement to create coding standards, among those of us who are interested, be a good idea? Am I being too particular, should I just let it go? Thank you all for your time. Note: Thanks everyone for the great feedback so far! To be clear, I don't want to dictate One Style To Rule Them All. I'm willing to concede my preferred way of doing something in favor of what suits everyone the best. I want consistency and I want this to be a democracy. I want it to be a group decision that everyone agrees on. True, not everyone will get their way, but I'm hoping that everyone will be mature enough to compromise for the betterment of the group. Note 2: Some people are getting caught up in the two examples I gave above. I'm more after the heart of the matter. It manifests itself with many examples: naming conventions, huge functions that should be broken up, should something go in a util or service, should something be a constant or injected, should we all use different versions of a dependency or the same, should an interface be used for this case, how should unit tests be set up, what should be unit tested, (Java specific) should we use annotations or external config. I could go on.

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  • What are the major challenges in creating a platform such as StackOverflow?

    - by gablin
    Let us assume you were to create a platform such as StackOverflow. It needs to be functional, fast and scalable, just like SO, in order to be successful. What are the major challenges you would face in such a task? I'm looking for technical challenges rather than problems such as how to advertise it and stuff like that. (I'm not looking for ways of creating a new site to challenge SO; I'm just interested in how difficult it would be to create it if it didn't already exist.)

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  • Haskell vs Erlang for web services

    - by Zachary K
    I am looking to start an experimental project using a functional language and am trying to decide beween Erlang and Haskell, and both have some points that I really like. I like Haskell's strong type system and purity. I have a feeling it will make it easier to write really reliable code. And I think that the power of haskell will make some of what I want to do much easier. On the minus side I get the feeling that some of the Frameworks for doing web stuff on Haskell such as Yesod are not as advanced as their Erlang counter parts. I rather like the Erlang approach to threads and to fault tollerence. I have a feeling that the scalability of Erlang could be a major plus. Which leeds to to my question, what has people's exerience been in implementing web application backends in both Haskell and Erlang. Are there packages for Haskell to provide some of the lightweight threads and actors that one has in Erlang?

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  • Should I avoid SharePoint Development in Visual Studio?

    - by SaphuA
    Hello, Not long ago I started an internship at a company that supplies SharePoint consultancy, hosting and development. While their consultancy seems to be pretty good and solid, I feel their development department lacks direction. The reason for this, most likely, is that they stopped outsourcing not too long ago. One thing that I've frequently bumped my head into is the following: My supervisor strongly insists that everything that can be done natively in SharePoint (somehow this includes editing xslt files in Designer) should be done in SharePoint. Even if this results in longer development time (at least when they make me write XSLT) and reduced usability. Her main arguments for this are: Better maintainability Editing the functionality doesn't require programming knowledge I feel the company is a little biassed and I am unable to get a decent discussion going. This is why I am looking for other places to get some responses on the subject (and not only on the arguments of my supervisor, but more on the subject in general). Kind regards

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  • CISCO Tapi with julmar atapi [closed]

    - by uma
    can we use julmar atapi for accessing cisco tapi/call manager functions?.. Is it a correct way to find solution. How to use cisco tapi with in .net application. Give me any sample code... Thanks in advance.. Sorry for the question with incomplete information. My requirement is, develop the interface for CUCM V8.6 (cisco unified call manager) with asp.net application. we need to communicate with CUCM to get the information about call details and force the user to enter authendication code. i got the information from web is, need C++ wrapper to access Tapi. Julmar Atapi is a free wrapper to access the Tapi. Our client need is , to use CISCO Tapi . My Question is , how to access CISCO Tapi from .Net Application. What is the Requirement? Is Julmar Atapi used to access CISCO Tapi? i want to use cisco FAC(Forced Authorization code) function. how to access this function from my application. Thanks in advance.

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  • In retrospect, has it been a good idea to use three-valued logic for SQL NULL comparisons?

    - by Heinzi
    In SQL, NULL means "unknown value". Thus, every comparison with NULL yields NULL (unknown) rather than TRUE or FALSE. From a conceptional point of view, this three-valued logic makes sense. From a practical point of view, every learner of SQL has, one time or another, made the classic WHERE myField = NULL mistake or learned the hard way that NOT IN does not do what one would expect when NULL values are present. It is my impression (please correct me if I am wrong) that the cases where this three-valued logic helps (e.g. WHERE myField IS NOT NULL AND myField <> 2 can be shortened to WHERE myField <> 2) are rare and, in those cases, people tend to use the longer version anyway for clarity, just like you would add a comment when using a clever, non-obvious hack. Is there some obvious advantage that I am missing? Or is there a general consensus among the development community that this has been a mistake?

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  • How can architects work with self-organizing Scrum teams?

    - by Martin Wickman
    An organization with a number of agile Scrum teams also has a small group of people appointed as "enterprise architects". The EA group acts as control and gatekeeper for quality and adherence to decisions. This leads to overlaps between the team decision and EA decisions. For instance, the team might want to use library X or want to use REST instead of SOAP, but the EA does not approve of that. Now, this can lead to frustration when team decisions are overruled. Taken far enough, it can potentially lead to a situation where the EA people "grabs" all power and the team ends up feeling demotivated and not very agile at all. The Scrum guides has this to say about it: Self-organizing: No one (not even the Scrum Master) tells the Development Team how to turn Product Backlog into Increments of potentially releasable functionality. Is that reasonable? Should the EA team be disbanded? Should the teams refuse or simply comply?

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  • As a C# developer, would you learn Java to develop for Android or use MonoDroid instead?

    - by Dan Tao
    I'd consider myself pretty well versed in C#. It's my language of choice at the moment, and it's where basically all my professional experience lies. Still, I'm puzzled by the existence of the MonoDroid project. My understanding has always been that C# and Java are very close. Like, if you know one, you can learn the other really quickly. So, as I've considered developing my first Android app, I just assumed I would familiarize myself with Java enough to get started and then just sort of learn as I go. Wouldn't this make more sense than using MonoDroid, which is likely to be less feature-rich than the Java Android SDK, and requires learning its own API (albeit a .NET API) anyway? I just feel like it would be better to learn a new language (and an extremely popular one at that) and get some experience in it—when it's so close to what you already know anyway—rather than stick with a technology you're experienced with, without gaining any more valuable skills. Maybe I'm grossly misrepresenting the average potential MonoDroid user. Maybe it's more for people who are experienced in Java and .NET and just prefer .NET. Or maybe (in fact it's likely) there are other factors I just haven't considered. I'm just wondering, why would you use MonoDroid instead of just developing for Android using Java?

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  • Adaptative Interface with Open GL and Machine Learning in c#

    - by Afnan
    For my Semester project i have to go for any Adaptative Interface Design. My language is c# and i have to Use OpenTK(Wrapper for Open GL). I have an idea that I should show Two points and some obstacles. and my subject which is user would drag an object from one place to the final place avoiding the Obstacles. and he can place obstacles randomly.My software should be made to learn some paths by doing test runs and then after learning program should be able to predict the shortest path. I donot know how stupid this idea sounds but it is just an idea.I need help regarding any ideas for adaptative interface possible small projects or if my idea is ok then please can you tell me what should be used to implement it? I mean that along with OpenGl for the Graphics what can i use for machine learning that helps me Thanks

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  • Rails noob - How to work on data stored in models

    - by Raghav Kanwal
    I'm a beginner to Ruby and Rails, and I have made a couple applications like a Microposts clone and a Todo-List for starters, but I'm starting work on another project. I've got 2 models - user and tracker, you log in via the username which is authenticated and you can log down data which is stored in the tracker table. The tracker has a column named "Calories" and I would like Rails to sum all of the values entered if they are on the same date, and output the result which is subtracted from, say 3000 in a new statement after the display of the model. I know what I'm talking about is just ruby code, im just not sure how to incorporate it. :( Could someone please guide me through this? And also link me to some guides/tutorials which teach working on data from models? Thank you :)

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  • EnOcean -> USB Serial Communication (C++)

    - by regorianer
    I guess it is not the right place to ask here for enocean specific details, but maybe I am doing something wrong by using serial connections and you can help me no matter if there is knowledge about this technology or not. I have a problem to communicate with the RCM152 Module. I have written a C++ program to communicate with the RCM152 by emulating packets of the PTM 200. I teach the RCM152 to listen to the following packets: [06/19/12 04:21:44.546] INFO: SENDING BYTE : 55 <-- start byte [06/19/12 04:21:44.546] INFO: SENDING BYTE : 00 <-- head begin [06/19/12 04:21:44.546] INFO: SENDING BYTE : 07 [06/19/12 04:21:44.546] INFO: SENDING BYTE : 07 [06/19/12 04:21:44.546] INFO: SENDING BYTE : 01 <-- head end [06/19/12 04:21:44.546] INFO: SENDING BYTE : 7a <-- CRC Check [06/19/12 04:21:44.546] INFO: SENDING BYTE : f6 <-- packet type [06/19/12 04:21:44.546] INFO: SENDING BYTE : 20 <-- My action (00 and 10 -> OFF, 20 and 30 -> ON) [06/19/12 04:21:44.546] INFO: SENDING BYTE : 00 <-- serial.byte 3 [06/19/12 04:21:44.546] INFO: SENDING BYTE : 24 <-- serial.byte 2 [06/19/12 04:21:44.546] INFO: SENDING BYTE : 21 <-- serial.byte 1 [06/19/12 04:21:44.546] INFO: SENDING BYTE : 87 <-- serial.byte 0 [06/19/12 04:21:44.546] INFO: SENDING BYTE : 30 <-- status [06/19/12 04:21:44.546] INFO: SENDING BYTE : 03 <-- 03 for send, 01 for receiver [06/19/12 04:21:44.546] INFO: SENDING BYTE : ff <-- begin destination [06/19/12 04:21:44.546] INFO: SENDING BYTE : ff [06/19/12 04:21:44.546] INFO: SENDING BYTE : ff [06/19/12 04:21:44.546] INFO: SENDING BYTE : ff <-- end destination [06/19/12 04:21:44.546] INFO: SENDING BYTE : ff <-- Transmission quality (sender ff) [06/19/12 04:21:44.546] INFO: SENDING BYTE : 00 [06/19/12 04:21:44.547] INFO: SENDING BYTE : 10 <-- CRC Check A PTM200 Device or a SG-FUS-24-230 Device are sending equivalent packets like: [06/19/12 04:30:31.106] INFO: Received Byte: 55 [06/19/12 04:30:31.106] INFO: Received Byte: 00 [06/19/12 04:30:31.106] INFO: Received Byte: 07 [06/19/12 04:30:31.106] INFO: Received Byte: 07 [06/19/12 04:30:31.106] INFO: Received Byte: 01 [06/19/12 04:30:31.106] INFO: Received Byte: 7a [06/19/12 04:30:31.106] INFO: Received Byte: f6 [06/19/12 04:30:31.106] INFO: Received Byte: 40 [06/19/12 04:30:31.106] INFO: Received Byte: 00 [06/19/12 04:30:31.106] INFO: Received Byte: 24 [06/19/12 04:30:31.106] INFO: Received Byte: 6c [06/19/12 04:30:31.106] INFO: Received Byte: 2f [06/19/12 04:30:31.106] INFO: Received Byte: 30 [06/19/12 04:30:31.106] INFO: Received Byte: 01 [06/19/12 04:30:31.106] INFO: Received Byte: ff [06/19/12 04:30:31.106] INFO: Received Byte: ff [06/19/12 04:30:31.108] INFO: Received Byte: ff [06/19/12 04:30:31.108] INFO: Received Byte: ff [06/19/12 04:30:31.108] INFO: Received Byte: 37 [06/19/12 04:30:31.108] INFO: Received Byte: 00 [06/19/12 04:30:31.108] INFO: Received Byte: d1 I can control the device connected to the RCM152 like I want to with my sending packets (thats a good fact and means that the RCM152 has learned my packets and can use them. Also the actions (0x10 - ON, 0x30 - OFF) are working fine), but the problem is, that no matter which serial I choose, the RCM152 reacts to these packets. I only want to have actions if the teached-in serial is send and all other packets with different serials to be ignored. The RCM152 is not reacting to the packets sent by the PTM200 nor by the SG-FUS-24-230 because these are not teached-in. Thats exactly what I want to have with the packets created myself. What am I doing wrong? The libraries I am using are these for C++ http://pvbrowser.de/pvbrowser/sf/manual/rllib/html/ The enocean EEP says: For this purpose of a determined relationship between transmitter and receiver each transmitting device has a unique Sender-ID which is part of each radio telegram. The receiving device detects from the Sender-ID whether the device is known, i.e., was already learned, or unknown. A telegram with unknown Sender-ID is disregarded.

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  • Visual web page designer for Django?

    - by Robert Oschler
    I'm just starting my Django learning so pardon me if any part of this question is off-base. I have done a lot of web searching for information on the equivalent of a visual web page designer for Django and I don't seem to be getting very far. I have experience with Delphi (Object Pascal), C, C++, Python, PHP, Java, and Javascript and have created and maintained several web sites that included MySQL database dependent content. For the longest time I've been using one of the standard WYSIWIG designers to design the actual web pages, with any needed back end programming done via Forms or AJAX calls that call server side PHP scripts. I have grown tired of the quirks, bugs, and other annoyances associated with the program. Also, I find myself hungry for the functionality and reliability a good MVC based framework would provide me so I could really express myself with custom code easily. So I am turning to Django/Python. However, I'm still a junkie for a good WYSIWIG designer for the layout of web pages. I know there are some out there that thrive on opening up a text editor, possibly with some code editor tools to assist, and pounding out pages. But I do adore a drag and drop editor for simple page layout, especially for things like embedded images, tables, buttons, etc. I found a few open source projects on GitHub but they seem to be focused on HTML web forms, not a generic web page editor. So can I get what I want here? The supreme goal would be to find not only a web page editor that creates Django compatible web pages, but if I dare say it, have a design editor that could add Python code stubs to various page elements in the style of the Delph/VCL or VB design editors. Note, I also have the Wing IDE Professional IDE, version 2.0. As a side note, if you know of any really cool, fun, or time-saving Python libraries that are designed for easy integration into Django please tell me about them. -- roschler

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  • What development terms come from the construction industry?

    - by Renesis
    When talking with colleagues about software design and development principles, I've noticed one of the most common sources for analogies is the construction industry. It would be quite useful to have a list of what programming/development terms and concepts are borrowed from construction industry? (And please provide a description or experiences regarding that topic.) [Credit to Programming concepts taken from the arts and humanities for the idea]

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  • clear explanation sought: throw() and stack unwinding

    - by Jerry Gagelman
    I'm not a programmer but have learned a lot watching others. I am writing wrapper classes to simplify things with a really technical API that I'm working with. Its routines return error codes, and I have a function that converts those to strings: static const char* LibErrString(int errno); For uniformity I decided to have member of my classes throw an exception when an error is encountered. I created a class: struct MyExcept : public std::exception { const char* errstr_; const char* what() const throw() {return errstr_;} MyExcept(const char* errstr) : errstr_(errstr) {} }; Then, in one of my classes: class Foo { public: void bar() { int err = SomeAPIRoutine(...); if (err != SUCCESS) throw MyExcept(LibErrString(err)); // otherwise... } }; The whole thing works perfectly: if SomeAPIRoutine returns an error, a try-catch block around the call to Foo::bar catches a standard exception with the correct error string in what(). Then I wanted the member to give more information: void Foo::bar() { char adieu[128]; int err = SomeAPIRoutine(...); if (err != SUCCESS) { std::strcpy(adieu,"In Foo::bar... "); std::strcat(adieu,LibErrString(err)); throw MyExcept((const char*)adieu); } // otherwise... } However, when SomeAPIRoutine returns an error, the what() string returned by the exception contains only garbage. It occurred to me that the problem could be due to adieu going out of scope once the throw is called. I changed the code by moving adieu out of the member definition and making it an attribute of the class Foo. After this, the whole thing worked perfectly: a try-call block around a call to Foo::bar that catches an exception has the correct (expanded) string in what(). Finally, my question: what exactly is popped off the stack (in sequence) when the exception is thrown in the if-block when the stack "unwinds?" As I mentioned above, I'm a mathematician, not a programmer. I could use a really lucid explanation of what goes onto the stack (in sequence) when this C++ gets converted into running machine code.

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