Search Results

Search found 30964 results on 1239 pages for 'tutor best practice'.

Page 152/1239 | < Previous Page | 148 149 150 151 152 153 154 155 156 157 158 159  | Next Page >

  • Should every class have its own namespace?

    - by thehouse
    Something that has been troubling me for a while: The current wisdom is that types should be kept in a namespace that only contains functions which are part of the type's non-member interface (see C++ Coding Standards Sutter and Alexandrescu or here) to prevent ADL pulling in unrelated definitions. Does this imply that all classes must have a namespace of their own? If we assume that a class may be augmented in the future by the addition of non-member functions, then it can never be safe to put two types in the same namespace as either one of them may introduce non-member functions that could interfere with the other. The reason I ask is that namespaces are becoming cumbersome for me. I'm writing a header-only library and I find myself using classes names such as project::component::class_name::class_name. Their implementations call helper functions but as these can't be in the same namespace they also have to be fully qualified!

    Read the article

  • What is the reason not to use select * ?

    - by Chris Lively
    I've seen a number of people claim that you should specifically name each column you want in your select query. Assuming I'm going to use all of the columns anyway, why would I not use SELECT *? Even considering the question from 9/24, I don't think this is an exact duplicate as I'm approaching the issue from a slightly different perspective. One of our principles is to not optimize before it's time. With that in mind, it seems like using SELECT * should be the preferred method until it is proven to be a resource issue or the schema is pretty much set in stone. Which, as we know, won't occur until development is completely done. That said, is there an overriding issue to not use SELECT *?

    Read the article

  • what if i keep my class members are public?

    - by anish
    In c++ instance variables are private by default,in Python variables are public by default i have two questions regarding the same:- 1: why Python have all the members are public by default? 2: People say you should your member data should be private what if i make my data to be public? what are the disadvantages of this approch? why it is a bad design?

    Read the article

  • Where to place the login/authentication related actions in MVC

    - by rogeriopvl
    I've searched around and found that when implementing an authentication module in MVC architecture some people opt to place the login related actions in the User controller while others place it in a controller dedicated to authentication only. In pseudo-java-like code: class UserController extends Controller { public login() { //... } } Accessed with http://mydomain.com/user/login. vs. class AuthController extends Controller { public login() { //... } } Accessed with http://mydomain.com/auth/login. I would like to know which approach is better, and why. That is, if there's really any difference at all. Thanks in advance.

    Read the article

  • How can I make an iterator that never ends?

    - by Soldier.moth
    I was just wondering what the easiest way to iterate over a set indefinitely, i.e. when it reaches the end it next(); calls the first object. I'm assuming that this is not an already predefined function in Java, so just looking for the easiest way to implement this in Java.

    Read the article

  • Python-based password tracker (or dictionary)

    - by Arrieta
    Hello: Where we work we need to remember about 10 long passwords which need to change every so often. I would like to create a utility which can potentially save these passwords in an encrypted file so that we can keep track of them. I can think of some sort of dictionary passwd = {'host1':'pass1', 'host2':'pass2'}, etc, but I don't know what to do about encryption (absolutely zero experience in the topic). So, my question is really two questions: Is there a Linux-based utility which lets you do that? If you were to program it in Python, how would you go about it? A perk of approach two, would be for the software to update the ssh public keys after the password has been changed (you know the pain of updating ~15 tokens once you change your password). As it can be expected, I have zero control over the actual network configuration and the management of scp keys. I can only hope to provide a simple utility to me an my very few coworkers so that, if we need to, we can retrieve a password on demand. Cheers.

    Read the article

  • how can I "force" a branch upon the trunk, in the case I can't "reintegrate"?

    - by davka
    We created a branch from the trunk on which a major refactoring was done. Meanwhile, the trunk advanced a few revisions with some fixes. We don't want these changes on the branch, so we don't want to "catch-up" merge the trunk to the branch, because we don't want to mix the old and new code. But without this I can't reintegrate the branch back to the trunk. Is there a way to impose the branch on the trunk "as-is"? (an idea I considered is to undo ("reverse-merge") the trunk back to the revision where the branch started, and then it is safe to merge it on branch - nothing should happen. Then I can reintegrate. What do you think?) thanks!

    Read the article

  • SELECT product from subclass: How many queries do I need?

    - by Stefano
    I am building a database similar to the one described here where I have products of different type, each type with its own attributes. I report a short version for convenience product_type ============ product_type_id INT product_type_name VARCHAR product ======= product_id INT product_name VARCHAR product_type_id INT -> Foreign key to product_type.product_type_id ... (common attributes to all product) magazine ======== magazine_id INT title VARCHAR product_id INT -> Foreign key to product.product_id ... (magazine-specific attributes) web_site ======== web_site_id INT name VARCHAR product_id INT -> Foreign key to product.product_id ... (web-site specific attributes) This way I do not need to make a huge table with a column for each attribute of different product types (most of which will then be NULL) How do I SELECT a product by product.product_id and see all its attributes? Do I have to make a query first to know what type of product I am dealing with and then, through some logic, make another query to JOIN the right tables? Or is there a way to join everything together? (if, when I retrieve the information about a product_id there are a lot of NULL, it would be fine at this point). Thank you

    Read the article

  • Which options do I have for Java process communication?

    - by Dmitriy Matveev
    We have a place in a code of such form: void processParam(Object param) { wrapperForComplexNativeObject result = jniCallWhichMayCrash(param); processResult(result); } processParam - method which is called with many different arguments. jniCallWhichMayCrash - a native method which is intended to do some complex processing of it's parameter and to create some complex object. It can crash in some cases. wrapperForComplexNativeObject - wrapper type generated by SWIG processResult - a method written in pure Java which processes it's parameter by creation of several kinds (by the kinds I'm not meaning classes, maybe some like hierarchies) of objects: 1 - Some non-unique objects which are referencing each other (from the same hierarchy), these objects can have duplicates created from the invocations of processParam() method with different parameter values. Since it's costly to keep all the duplicates it's necessary to cache them. 2 - Some unique objects which are referencing each other (from the same hierarchy) and some of the objects of 1st kind. After processParam is executed for each of the arguments from some set the data created in processResult will be processed together. The problem is in fact that jniCallWhichMayCrash method may crash the entire JVM and this will be very bad. The reason of crash may be such that it can happen for one argument value and not for the other. We've decided that it's better to ignore crashes inside of JVM and just skip some chunks of data when such crashes occur. In order to do this we should run processParam function inside of separate process and pass the result somehow (HOW? HOW?! This is a question) to the main process and in case of any crashes we will only lose some part of data (It's ok) without lose of everything else. So for now the main problem is implementation of transport between different processes. Which options do I have? I can think about serialization and transmitting of binary data by the streams, but serialization may be not very fast due to object complexity. Maybe I have some other options of implementing this?

    Read the article

  • Is there any difference between var name = function() {} & function name() {} in Javascript?

    - by Fletcher Moore
    Suppose we are inside a function and not in the global namespace. function someGlobalFunction() { var utilFunction1 = function() { } function utilFunction2 () { } utilFunction1(); utilFunction2(); } Are these synonymous? And do these functions completely cease to exist when someGlobalFunction returns? Should I prefer one or the other for readability or some other reason?

    Read the article

  • Is it advisable to have an interface as the return type?

    - by wb
    I have a set of classes with the same functions but with different logic. However, each class function can return a number of objects. It is safe to set the return type as the interface? Each class (all using the same interface) is doing this with different business logic. protected IMessage validateReturnType; <-- This is in an abstract class public bool IsValid() <-- This is in an abstract class { return (validateReturnType.GetType() == typeof(Success)); } public IMessage Validate() { if (name.Length < 5) { validateReturnType = new Error("Name must be 5 characters or greater."); } else { validateReturnType = new Success("Name is valid."); } return validateReturnType; } Are there any pitfalls with unit testing the return type of an function? Also, is it considered bad design to have functions needing to be run in order for them to succeed? In this example, Validate() would have to be run before IsValid() or else IsValid() would always return false. Thank you.

    Read the article

  • Comparing objects and inheritance

    - by ereOn
    Hi, In my program I have the following class hierarchy: class Base // Base is an abstract class { }; class A : public Base { }; class B : public Base { }; I would like to do the following: foo(const Base& one, const Base& two) { if (one == two) { // Do something } else { // Do something else } } I have issues regarding the operator==() here. Of course comparing an instance A and an instance of B makes no sense but comparing two instances of Base should be possible. (You can't compare a Dog and a Cat however you can compare two Animals) I would like the following results: A == B = false A == A = true or false, depending on the effective value of the two instances B == B = true or false, depending on the effective value of the two instances My question is: is this a good design/idea ? Is this even possible ? What functions should I write/overload ? My apologies if the question is obviously stupid or easy, I have some serious fever right now and my thinking abilities are somewhat limited :/ Thank you.

    Read the article

  • How to avoid nested functions when using AJAX?

    - by Fletcher Moore
    Sequential Asynchronous calls are gross. Is there a more readable solution? The problem is this is hard to follow: ajaxOne(function() { // do something ajaxTwo(function() { // do something ajaxThree() }); }); where the anonymous functions are callbacks that are called on server response. I'm using a third party API to make the AJAX calls, so I need a generic solution.

    Read the article

  • #Define Compiler Directive in C#

    - by pm_2
    In C, I could declare a compiler directive as follows: #define MY_NUMBER 10 However, in C#, I only appear to be able to do this: #define MY_NUMBER Which is obviously useless in this case. Is this correct, or am I doing something wrong? If not, can anyone suggest a way of doing this, either at namespace or solution level? I thought of maybe creating a static class, but that seems to be overkill for one value.

    Read the article

  • Best approach to store login credentials for website

    - by Zerotoinfinite
    I have created a site in ASP.NET 3.5 & I have only 2 or 3 user login IDs who can login to the website. What would be the best way to save these login details? Which of these approaches, or others, would be most suitable? Using Forms Authentication, and saving credentials (username and password) in web.config to create a text file in directory and modify it Which approach is best from a security and maintenance perspective? What other approaches are suitable for a login system for ASP.NET?

    Read the article

  • To change checkbox text or to not change?

    - by Axarydax
    Hi, I'm having an argument with a co-worker, and I'm trying to convince him that it's a bad idea to change checkbox text (label) according to the checkbox state. For example, we have a combobox that automatically picks selected value (and is disabled) when checkbox next to it is checked and is enabled when checkbox is cleared. His idea is to show Autoselect when checkbox is checked and Manual select when it's cleared. I'm sure that this will confuse the user as users tend to think that checking a checkbox next to a verb will make it true, only to find that the label has changed to something else. What is your opinion on this matter? P.S. I remember reading about changing checkbox text somewhere, in a book or blog article, but can't remember where. It would be great to have this in writing :-)

    Read the article

  • Symfony 1.3: Any opinion about this code? Coud be shorter or better?

    - by user248959
    Hi, I need your opinion about this code below. I have a list of messages: each message has a link that change the state of the message (read - non read). In the partial "_message" i have this: <div class="switching_link" id="switching_link_<?php echo $message ?>"> echo include_partial('link_switch_state', array('message' => $message)) </div> In the partial "_link_switch_state" i have this: if((int)$message->getState() == 1) { $string_state_message="non read"; } else { $string_state_message="read"; } echo link_to_remote('Mark as '.$string_state_message, array( 'url' => 'message/switchState?id='.$message->getId(), 'update' => 'switching_link_'.$message, "complete" => "switchClassMessage('$message');", )); And in message/actions/actions.class.php i have this: public function executeSwitchState(sfWebRequest $request) { // searching the message we want to change its state. $this->messages = Doctrine::getTable('Message')->findById($request->getParameter('id')); // changing the state of the message. if($this->messages[0]->getState() == 1) { $this->messages[0]->setState(0); } else { $this->messages[0]->setState(1); } $this->messages[0]->save(); // rendering the partial that shows the link ("Mark as read/non read"). return $this->renderPartial('mensaje/link_switch_state', array( 'message' => $this->messages[0])); } Regards Javi

    Read the article

  • How do I get mercurial to show the diff during `hg com`?

    - by Kev
    Is there a way to configure hg com so that in the commit message file that pops up in the external editor, instead of just showing which files were changed (in the HG: lines) it actually shows the full diff? I'd rather view the output and compose my commit message simultaneously from the comfort of my text editor as opposed to doing hg diff on the command line separately beforehand.

    Read the article

  • Does MVC replace traditional manually created BLL?

    - by used2could
    I'm used to creating the UI, BLL, DAL by hand (some times I've used LINQ-to-SQL or SubSonic for the DAL). I've done several small projects using MVC since its release. On these projects I've still continued to write a BLL and DAL by hand and then incorporate those into the MVC's models/controllers. I'm looking to optimize my time on projects this seems like overkill and a potential waste of time. Question Would it be acceptable to roll a DAL such as SubSonic and directly use it in the Models/Controllers of my MVC web app? Now the models & controllers would act as the BLL. I just see this as a major timesaver to not have to worry about another tier. UPDATE: I just wanted to add that my concern isn't really with the DAL (I frequently use SubSonic and NH) but rather focus on the BLL. Sorry for the confusion.

    Read the article

  • Static method,new thread performance question

    - by ylazez
    Hey guys i just have two questions about two methods used in many controllers/servlets in my app: 1-what is the difference between calling a static method in a util class or a non static method (like methods dealing with dates i.e getting current time,converting between timezones), which is better ? 2-what is the difference between calling a method(contain too many logic like sending emails) in the controller directly or running this method in a different thread ?

    Read the article

< Previous Page | 148 149 150 151 152 153 154 155 156 157 158 159  | Next Page >