Search Results

Search found 1281 results on 52 pages for 'stl containers'.

Page 9/52 | < Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >

• Dependency Injection/IoC container practices when writing frameworks

  - by Dave Hillier

  I've used various IoC containers (Castle.Windsor, Autofac, MEF, etc) for .Net in a number of projects. I have found they tend to encourage a number of bad practices. Are there any established practices for IoC container use, particularly when providing a platform/framework? My aim as a framework writer is to make code as simple and as easy to use as possible. I'd rather write one line of code to construct an object than ten or even just two. For example, a couple of code smells that I've noticed and don't have good suggestions to: Large number of parameters (5) for constructors. Creating services tends to be complex; all of the dependencies are injected via the constructor - despite the fact that the components are rarely optional (except for maybe in testing). Lack of private and internal classes; this one may be a specific limitation of using C# and Silverlight, but I'm interested in how it is solved. It's difficult to tell what a frameworks interface is if all the classes are public; it allows me access to private parts that I probably shouldnt touch. Coupling the object lifecycle to the IoC container. It is often difficult to manually construct the dependencies required to create objects. Object lifecycle is too often managed by the IoC framework. I've seen projects where most classes are registered as Singletons. You get a lack of explicit control and are also forced to manage the internals (it relates to the above point, all classes are public and you have to inject them). For example, .Net framework has many static methods. such as, DateTime.UtcNow. Many times I have seen this wrapped and injected as a construction parameter. Depending on concrete implementation makes my code hard to test. Injecting a dependency makes my code hard to use - particularly if the class has many parameters. How do I provide both a testable interface, as well as one that is easy to use? What are the best practices?

  Read the article

• How to build a Singleton-like dependency injector replacement (Php)

  - by Erparom

  I know out there are a lot of excelent containers, even frameworks almost entirely DI based with good strong IoC classes. However, this doesn't help me to "define" a new pattern. (This is Php code but understandable to anyone) Supose we have: //Declares the singleton class bookSingleton { private $author; private static $bookInstance; private static $isLoaned = FALSE; //The private constructor private function __constructor() { $this->author = "Onecrappy Writer Ofcheap Novels"; } //Sets the global isLoaned state and also gets self instance public static function loanBook() { if (self::$isLoaned === FALSE) { //Book already taken, so return false return FALSE; } else { //Ok, not loaned, lets instantiate (if needed and loan) if (!isset(self::$bookInstance)) { self::$bookInstance = new BookSingleton(); } self::$isLoaned = TRUE; } } //Return loaned state to false, so another book reader can take the book public function returnBook() { $self::$isLoaned = FALSE; } public function getAuthor() { return $this->author; } } Then we get the singelton consumtion class: //Consumes the Singleton class BookBorrower() { private $borrowedBook; private $haveBookState; public function __construct() { this->haveBookState = FALSE; } //Use the singelton-pattern behavior public function borrowBook() { $this->borrowedBook = BookSingleton::loanBook(); //Check if was successfully borrowed if (!this->borrowedBook) { $this->haveBookState = FALSE; } else { $this->haveBookState = TRUE; } } public function returnBook() { $this->borrowedBook->returnBook(); $this->haveBookState = FALSE; } public function getBook() { if ($this->haveBookState) { return "The book is loaned, the author is" . $this->borrowedbook->getAuthor(); } else { return "I don't have the book, perhaps someone else took it"; } } } At last, we got a client, to test the behavior function __autoload($class) { require_once $class . '.php'; } function write ($whatever,$breaks) { for($break = 0;$break<$breaks;$break++) { $whatever .= "\n"; } echo nl2br($whatever); } write("Begin Singleton test", 2); $borrowerJuan = new BookBorrower(); $borrowerPedro = new BookBorrower(); write("Juan asks for the book", 1); $borrowerJuan->borrowBook(); write("Book Borrowed? ", 1); write($borrowerJuan->getAuthorAndTitle(),2); write("Pedro asks for the book", 1); $borrowerPedro->borrowBook(); write("Book Borrowed? ", 1); write($borrowerPedro->getAuthorAndTitle(),2); write("Juan returns the book", 1); $borrowerJuan->returnBook(); write("Returned Book Juan? ", 1); write($borrowerJuan->getAuthorAndTitle(),2); write("Pedro asks again for the book", 1); $borrowerPedro->borrowBook(); write("Book Borrowed? ", 1); write($borrowerPedro->getAuthorAndTitle(),2); This will end up in the expected behavior: Begin Singleton test Juan asks for the book Book Borrowed? The book is loaned, the author is = Onecrappy Writer Ofcheap Novels Pedro asks for the book Book Borrowed? I don't have the book, perhaps someone else took it Juan returns the book Returned Book Juan? I don't have the book, perhaps someone else took it Pedro asks again for the book Book Borrowed? The book is loaned, the author is = Onecrappy Writer Ofcheap Novels So I want to make a pattern based on the DI technique able to do exactly the same, but without singleton pattern. As far as I'm aware, I KNOW I must inject the book inside "borrowBook" function instead of taking a static instance: public function borrowBook(BookNonSingleton $book) { if (isset($this->borrowedBook) || $book->isLoaned()) { $this->haveBook = FALSE; return FALSE; } else { $this->borrowedBook = $book; $this->haveBook = TRUE; return TRUE; } } And at the client, just handle the book: $borrowerJuan = new BookBorrower(); $borrowerJuan-borrowBook(new NonSingletonBook()); Etc... and so far so good, BUT... Im taking the responsability of "single instance" to the borrower, instead of keeping that responsability inside the NonSingletonBook, that since it has not anymore a private constructor, can be instantiated as many times... making instances on each call. So, What does my NonSingletonBook class MUST be in order to never allow borrowers to have this same book twice? (aka) keep the single instance. Because the dependency injector part of the code (borrower) does not solve me this AT ALL. Is it needed the container with an "asShared" method builder with static behavior? No way to encapsulate this functionallity into the Book itself? "Hey Im a book and I shouldn't be instantiated more than once, I'm unique"

  Read the article

• Advice when using COM Object/CComPtr and the STL

  - by YoungPony

  Hello, I am doing some COM related things with directshow such as: typedef CComPtr<IBaseFilter> AutoIBaseFilterPtr; map<CString, AutoIBaseFilterPtr> _filterMap; To store a list of directShow related com objects and their friendly name. After finding this article (See:Problem 2) on how changes in VC10 compiler might effect previously OK code, I am wondering if there are any more things to watch out for when mixing the STL and CComPtr or prehaps just mixing the STL and COM in general. Any tips would be greatly appreciated, thanks

  Read the article

• What is the relation between ContentPane and JPanel?

  - by Roman

  I found one example in which buttons are added to panels (instances of JPanel) then panels are added to the the containers (instances generated by getContentPane) and then containers are, by the construction, included into the JFrame (the windows). I tried two things: I got rid of the containers. In more details, I added buttons to a panel (instance of JPanel) and then I added the panel to the windows (instance of JFrame). It worked fine. I got rid of the panels. In more details, I added buttons directly to the container and then I added the container to the window (instance of JFrame). So, I do not understand two things. Why do we have two competing mechanism to do the same things. What is the reason to use containers in combination with the panels (JPanel)? (For example, what for we include buttons in JPanels and then we include JPanels in the Containers). Can we include JPanel in JPanel? Can we include a container in container?

  Read the article

• interview quesions book on C++. STL and boost

  - by hitech

  I w'd really appreciate if somebody suggest me any book which has good interview questions on C++, STL and boost?

  Read the article

• WPF: Is VerticalAlignment inherited by nested containers?

  - by zxcvbnm

  I'd like to have the nested containers inherit that property, but when I set it in the outermost one I'm not sure if it's working. It either is working but I'm not getting the results I want, or maybe I'd have to set up a property somewhere for it to carry. Assuming that a) it is possible to do it and b) I'd have to change a property somewhere, would that have any side effects I should be aware of?

  Read the article

• How to manage IoC containers in tests?

  - by frosty

  I'm very new to testing and IoC containers and have two projects: MySite.Website (MVC) MySite.WebsiteTest Currently I have an IoC container in my website. Should I recreate another IoC container for my test? Or is there a way to use the IoC in both?

  Read the article

• C++ containers on classes, returning pointers

  - by otneil

  Hello, I'm having some trouble to find the best way to accomplish what I have in mind due to my inexperience. I have a class where I need to a vector of objects. So my first question will be: is there any problem having this: vector< AnyType container* and then on the constructor initialize it with new (and deleting it on the destructor)? Another question is: if this vector is going to store objects, shouldn't it be more like vector< AnyTipe* so they could be dynamically created? In that case how would I return an object from a method and how to avoid memory leaks (trying to use only STL)?

  Read the article

• Can I use MFC objects in STL containers?

  - by Jesse Stimpson

  The following code doesn't compile for me in MSVC2005: std::vector<CMenu> vec(10); CMenu is an MFC menu object (such as a context menu). Through some testing I learned that CMenu does not have a public copy constructor. To do what I wanted to do, I needed to use a dynamic array. CMenu* menus = new CMenu[10]; // ... delete [] menus; Of course, now I've lost all the benefits of using an STL container. Do I have any other options?

  Read the article

• Is it bad practice to make an iterator that is aware of its own end

  - by aaronman

  For some background of why I am asking this question here is an example. In python the method chain chains an arbitrary number of ranges together and makes them into one without making copies. Here is a link in case you don't understand it. I decided I would implement chain in c++ using variadic templates. As far as I can tell the only way to make an iterator for chain that will successfully go to the next container is for each iterator to to know about the end of the container (I thought of a sort of hack in where when != is called against the end it will know to go to the next container, but the first way seemed easier and safer and more versatile). My question is if there is anything inherently wrong with an iterator knowing about its own end, my code is in c++ but this can be language agnostic since many languages have iterators. #ifndef CHAIN_HPP #define CHAIN_HPP #include "iterator_range.hpp" namespace iter { template <typename ... Containers> struct chain_iter; template <typename Container> struct chain_iter<Container> { private: using Iterator = decltype(((Container*)nullptr)->begin()); Iterator begin; const Iterator end;//never really used but kept it for consistency public: chain_iter(Container & container, bool is_end=false) : begin(container.begin()),end(container.end()) { if(is_end) begin = container.end(); } chain_iter & operator++() { ++begin; return *this; } auto operator*()->decltype(*begin) { return *begin; } bool operator!=(const chain_iter & rhs) const{ return this->begin != rhs.begin; } }; template <typename Container, typename ... Containers> struct chain_iter<Container,Containers...> { private: using Iterator = decltype(((Container*)nullptr)->begin()); Iterator begin; const Iterator end; bool end_reached = false; chain_iter<Containers...> next_iter; public: chain_iter(Container & container, Containers& ... rest, bool is_end=false) : begin(container.begin()), end(container.end()), next_iter(rest...,is_end) { if(is_end) begin = container.end(); } chain_iter & operator++() { if (begin == end) { ++next_iter; } else { ++begin; } return *this; } auto operator*()->decltype(*begin) { if (begin == end) { return *next_iter; } else { return *begin; } } bool operator !=(const chain_iter & rhs) const { if (begin == end) { return this->next_iter != rhs.next_iter; } else return this->begin != rhs.begin; } }; template <typename ... Containers> iterator_range<chain_iter<Containers...>> chain(Containers& ... containers) { auto begin = chain_iter<Containers...>(containers...); auto end = chain_iter<Containers...>(containers...,true); return iterator_range<chain_iter<Containers...>>(begin,end); } } #endif //CHAIN_HPP

  Read the article

• Are IoC containers about configuration files?

  - by Jader Dias

  Recently I developed a performance tester console application, with no UI, with the help of a IoC containter (Castle-Windsor-Microkernel). This library enabled me to let the user choose which test(s) to run, simply by changing the configuration file. Have I realized what IoC containers are about? I'm not sure. Even Joel said here on SO that IoC are difficult to understand. From my example, what do you conclude? Am I using IoC container for exactly what they were designed for? Or I am just using one of its secondary features?

  Read the article

• Avoiding seasonality assumption for stl() or decompose() in R

  - by user303922

  Hello everybody, I have high frequency commodity price data that I need to analyze. My objective is to not assume any seasonal component and just identify a trend. Here is where I run into problems with R. There are two main functions that I know of to analyze this time series: decompose() and stl(). The problem is that they both take a ts object type with a frequency parameter greater than or equal to 2. Is there some way I can assume a frequency of 1 per unit time and still analyze this time series using R? I'm afraid that if I assume frequency greater than 1 per unit time, and seasonality is calculated using the frequency parameter, then my forecasts are going to depend on that assumption. names(crude.data)=c('Date','Time','Price') names(crude.data) freq = 2 win.graph() plot(crude.data$Time,crude.data$Price, type="l") crude.data$Price = ts(crude.data$Price,frequency=freq) I want frequency to be 1 per unit time but then decompose() and stl() don't work! dim(crude.data$Price) decom = decompose(crude.data$Price) win.graph() plot(decom$random[2:200],type="line") acf(decom$random[freq:length(decom$random-freq)]) Thank you.

  Read the article

• STL vector performance

  - by iAdam

  STL vector class stores a copy of the object using copy constructor each time I call push_back. Wouldn't it slow down the program? I can have a custom linkedlist kind of class which deals with pointers to objects. Though it would not have some benefits of STL but still should be faster. See this code below: #include <vector> #include <iostream> #include <cstring> using namespace std; class myclass { public: char* text; myclass(const char* val) { text = new char[10]; strcpy(text, val); } myclass(const myclass& v) { cout << "copy\n"; //copy data } }; int main() { vector<myclass> list; myclass m1("first"); myclass m2("second"); cout << "adding first..."; list.push_back(m1); cout << "adding second..."; list.push_back(m2); cout << "returning..."; myclass& ret1 = list.at(0); cout << ret1.text << endl; return 0; } its output comes out as: adding first...copy adding second...copy copy The output shows the copy constructor is called both times when adding and when retrieving the value even then. Does it have any effect on performance esp when we have larger objects?

  Read the article

• Business Objects - Containers or functional?

  - by Walter

  Where I work, we've gone back and forth on this subject a number of times and are looking for a sanity check. Here's the question: Should Business Objects be data containers (more like DTOs) or should they also contain logic that can perform some functionality on that object. Example - Take a customer object, it probably contains some common properties (Name, Id, etc), should that customer object also include functions (Save, Calc, etc.)? One line of reasoning says separate the object from the functionality (single responsibility principal) and put the functionality in a Business Logic layer or object. The other line of reasoning says, no, if I have a customer object I just want to call Customer.Save and be done with it. Why do I need to know about how to save a customer if I'm consuming the object? Our last two projects have had the objects separated from the functionality, but the debate has been raised again on a new project. Which makes more sense? EDIT These results are very similar to our debates. One vote to one side or another completely changes the direction. Does anyone else want to add their 2 cents? EDIT Eventhough the answer sampling is small, it appears that the majority believe that functionality in a business object is acceptable as long as it is simple but persistence is best placed in a separate class/layer. We'll give this a try. Thanks for everyone's input...

  Read the article

• Generic factory of generic containers

  - by Feuermurmel

  I have a generic abstract class Factory<T> with a method createBoxedInstance() which returns instances of T created by implementations of createInstance() wrapped in the generic container Box<T>. abstract class Factory<T> { abstract T createInstance(); public final Box<T> createBoxedInstance() { return new Box<T>(createInstance()); } public final class Box<T> { public final T content; public Box(T content) { this.content = content; } } } At some points I need a container of type Box<S> where S is an ancestor of T. Is it possible to make createBoxedInstance() itself generic so that it will return instances of Box<S> where S is chosen by the caller? Sadly, defining the function as follows does not work as a type parameter cannot be declared using the super keyword, only used. public final <S super T> Box<S> createBoxedInstance() { return new Box<S>(createInstance()); } The only alternative I see, is to make all places that need an instance of Box<S> accept Box<? extends S> which makes the container's content member assignable to S. Is there some way around this without re-boxing the instances of T into containers of type Box<S>? (I know I could just cast the Box<T> to a Box<S> but I would feel very, very guilty.)

  Read the article

• Improving Manageability of Virtual Environments

  - by Jeff Victor

  Boot Environments for Solaris 10 Branded Zones Until recently, Solaris 10 Branded Zones on Solaris 11 suffered one notable regression: Live Upgrade did not work. The individual packaging and patching tools work correctly, but the ability to upgrade Solaris while the production workload continued running did not exist. A recent Solaris 11 SRU (Solaris 11.1 SRU 6.4) restored most of that functionality, although with a slightly different concept, different commands, and without all of the feature details. This new method gives you the ability to create and manage multiple boot environments (BEs) for a Solaris 10 Branded Zone, and modify the active or any inactive BE, and to do so while the production workload continues to run. Background In case you are new to Solaris: Solaris includes a set of features that enables you to create a bootable Solaris image, called a Boot Environment (BE). This newly created image can be modified while the original BE is still running your workload(s). There are many benefits, including improved uptime and the ability to reboot into (or downgrade to) an older BE if a newer one has a problem. In Solaris 10 this set of features was named Live Upgrade. Solaris 11 applies the same basic concepts to the new packaging system (IPS) but there isn't a specific name for the feature set. The features are simply part of IPS. Solaris 11 Boot Environments are not discussed in this blog entry. Although a Solaris 10 system can have multiple BEs, until recently a Solaris 10 Branded Zone (BZ) in a Solaris 11 system did not have this ability. This limitation was addressed recently, and that enhancement is the subject of this blog entry. This new implementation uses two concepts. The first is the use of a ZFS clone for each BE. This makes it very easy to create a BE, or many BEs. This is a distinct advantage over the Live Upgrade feature set in Solaris 10, which had a practical limitation of two BEs on a system, when using UFS. The second new concept is a very simple mechanism to indicate the BE that should be booted: a ZFS property. The new ZFS property is named com.oracle.zones.solaris10:activebe (isn't that creative? ). It's important to note that the property is inherited from the original BE's file system to any BEs you create. In other words, all BEs in one zone have the same value for that property. When the (Solaris 11) global zone boots the Solaris 10 BZ, it boots the BE that has the name that is stored in the activebe property. Here is a quick summary of the actions you can use to manage these BEs: To create a BE: Create a ZFS clone of the zone's root dataset To activate a BE: Set the ZFS property of the root dataset to indicate the BE To add a package or patch to an inactive BE: Mount the inactive BE Add packages or patches to it Unmount the inactive BE To list the available BEs: Use the "zfs list" command. To destroy a BE: Use the "zfs destroy" command. Preparation Before you can use the new features, you will need a Solaris 10 BZ on a Solaris 11 system. You can use these three steps - on a real Solaris 11.1 server or in a VirtualBox guest running Solaris 11.1 - to create a Solaris 10 BZ. The Solaris 11.1 environment must be at SRU 6.4 or newer. Create a flash archive on the Solaris 10 system s10# flarcreate -n s10-system /net/zones/archives/s10-system.flar Configure the Solaris 10 BZ on the Solaris 11 system s11# zonecfg -z s10z Use 'create' to begin configuring a new zone. zonecfg:s10z create -t SYSsolaris10 zonecfg:s10z set zonepath=/zones/s10z zonecfg:s10z exit s11# zoneadm list -cv ID NAME STATUS PATH BRAND IP 0 global running / solaris shared - s10z configured /zones/s10z solaris10 excl Install the zone from the flash archive s11# zoneadm -z s10z install -a /net/zones/archives/s10-system.flar -p You can find more information about the migration of Solaris 10 environments to Solaris 10 Branded Zones in the documentation. The rest of this blog entry demonstrates the commands you can use to accomplish the aforementioned actions related to BEs. New features in action Note that the demonstration of the commands occurs in the Solaris 10 BZ, as indicated by the shell prompt "s10z# ". Many of these commands can be performed in the global zone instead, if you prefer. If you perform them in the global zone, you must change the ZFS file system names. Create The only complicated action is the creation of a BE. In the Solaris 10 BZ, create a new "boot environment" - a ZFS clone. You can assign any name to the final portion of the clone's name, as long as it meets the requirements for a ZFS file system name. s10z# zfs snapshot rpool/ROOT/zbe-0@snap s10z# zfs clone -o mountpoint=/ -o canmount=noauto rpool/ROOT/zbe-0@snap rpool/ROOT/newBE cannot mount 'rpool/ROOT/newBE' on '/': directory is not empty filesystem successfully created, but not mounted You can safely ignore that message: we already know that / is not empty! We have merely told ZFS that the default mountpoint for the clone is the root directory. List the available BEs and active BE Because each BE is represented by a clone of the rpool/ROOT dataset, listing the BEs is as simple as listing the clones. s10z# zfs list -r rpool/ROOT NAME USED AVAIL REFER MOUNTPOINT rpool/ROOT 3.55G 42.9G 31K legacy rpool/ROOT/zbe-0 1K 42.9G 3.55G / rpool/ROOT/newBE 3.55G 42.9G 3.55G / The output shows that two BEs exist. Their names are "zbe-0" and "newBE". You can tell Solaris that one particular BE should be used when the zone next boots by using a ZFS property. Its name is com.oracle.zones.solaris10:activebe. The value of that property is the name of the clone that contains the BE that should be booted. s10z# zfs get com.oracle.zones.solaris10:activebe rpool/ROOT NAME PROPERTY VALUE SOURCE rpool/ROOT com.oracle.zones.solaris10:activebe zbe-0 local Change the active BE When you want to change the BE that will be booted next time, you can just change the activebe property on the rpool/ROOT dataset. s10z# zfs get com.oracle.zones.solaris10:activebe rpool/ROOT NAME PROPERTY VALUE SOURCE rpool/ROOT com.oracle.zones.solaris10:activebe zbe-0 local s10z# zfs set com.oracle.zones.solaris10:activebe=newBE rpool/ROOT s10z# zfs get com.oracle.zones.solaris10:activebe rpool/ROOT NAME PROPERTY VALUE SOURCE rpool/ROOT com.oracle.zones.solaris10:activebe newBE local s10z# shutdown -y -g0 -i6 After the zone has rebooted: s10z# zfs get com.oracle.zones.solaris10:activebe rpool/ROOT rpool/ROOT com.oracle.zones.solaris10:activebe newBE local s10z# zfs mount rpool/ROOT/newBE / rpool/export /export rpool/export/home /export/home rpool /rpool Mount the original BE to see that it's still there. s10z# zfs mount -o mountpoint=/mnt rpool/ROOT/zbe-0 s10z# ls /mnt Desktop export platform Documents export.backup.20130607T214951Z proc S10Flar home rpool TT_DB kernel sbin bin lib system boot lost+found tmp cdrom mnt usr dev net var etc opt Patch an inactive BE At this point, you can modify the original BE. If you would prefer to modify the new BE, you can restore the original value to the activebe property and reboot, and then mount the new BE to /mnt (or another empty directory) and modify it. Let's mount the original BE so we can modify it. (The first command is only needed if you haven't already mounted that BE.) s10z# zfs mount -o mountpoint=/mnt rpool/ROOT/zbe-0 s10z# patchadd -R /mnt -M /var/sadm/spool 104945-02 Note that the typical usage will be: Create a BE Mount the new (inactive) BE Use the package and patch tools to update the new BE Unmount the new BE Reboot Delete an inactive BE ZFS clones are children of their parent file systems. In order to destroy the parent, you must first "promote" the child. This reverses the parent-child relationship. (For more information on this, see the documentation.) The original rpool/ROOT file system is the parent of the clones that you create as BEs. In order to destroy an earlier BE that is that parent of other BEs, you must first promote one of the child BEs to be the ZFS parent. Only then can you destroy the original BE. Fortunately, this is easier to do than to explain: s10z# zfs promote rpool/ROOT/newBE s10z# zfs destroy rpool/ROOT/zbe-0 s10z# zfs list -r rpool/ROOT NAME USED AVAIL REFER MOUNTPOINT rpool/ROOT 3.56G 269G 31K legacy rpool/ROOT/newBE 3.56G 269G 3.55G / Documentation This feature is so new, it is not yet described in the Solaris 11 documentation. However, MOS note 1558773.1 offers some details. Conclusion With this new feature, you can add and patch packages to boot environments of a Solaris 10 Branded Zone. This ability improves the manageability of these zones, and makes their use more practical. It also means that you can use the existing P2V tools with earlier Solaris 10 updates, and modify the environments after they become Solaris 10 Branded Zones.

  Read the article

• it is a good approach to implement dependency injection in a desktop app?

  - by luis_laurent

  Well, the thing is that I am just about to create a Desktop App (with .NET windows forms) And now I just wonder if it would be really a wise choise to use any IoC (StructureMap,Ninject,Spring .Net), I have used them before for Asp.Net web applications but what makes me doubt now is the fact that working with windows forms my business entities will persist when I navigate through tabs and unlike than web forms or mvc apps where it would be necesary to inject my business entity for every new request that is performed, I mean this because of the Asp.Net page life cycle where is performed the initialization and controls instantiation. Maybe I am misunderstanding the point of using an IoC, so please tell me what do you think would be a better choise?

  Read the article

• What are some C++ Standard Library usage best practices?

  - by apphacker

  I'm learning C++ and the book I'm reading (The C++ Programming Language) says to not reinvent the wheel, to rely on the standard libraries. In C, I often end up creating a linked list, and link list iteration over and over again (maybe I'm doing that wrong not sure), so the ideas of containers available in C++, and strings, and algorithms really appeal to me. However I have read a little online, and heard some criticisms from my friends and coworkers about STL, so I thought I maybe I'd pick some brains here. What are some best practices for using STL, and what lessons have you learned about STL?

  Read the article

• Composite pattern in C++ problem

  - by annouk

  Hello! I have to work with an application in C++ similar to a phone book: the class Agenda with an STL list of Contacts.Regarding the contacts hierarchy,there is a base-class named Contact(an abstract one),and the derived classes Friend and Acquaintance(the types of contact). These classes have,for instance, a virtual method called getName,which returns the name of the contact. Now I must implement the Composite pattern by adding another type of contact,Company(being derived from Contact),which also contains a collection of Contacts(an STL list as well),that can be either of the "leaf" type(Friends or Acquaintances),or they can be Companies as well. Therefore,Company is the Compound type. The question is: how and where can I implement an STL find_if to search the contact with a given name(via getName function or suggest me smth else) both among the "leaf"-type Contact and inside the Company collection? In other words,how do I traverse the tree in order to find possible matches there too,using an uniform function definition? I hope I was pretty clear...

  Read the article

• Calculate volume based on STL file

  - by plancake

  Just wondering if anyone had a simple, efficient way of calculating the volume of a stereolithographic file (STL)? And rendering this in a Windows Form Control?

  Read the article

• java Map keyset equivalent for C++ STL Map

  - by Akshay Bhat

  I tried searching documentation but couldn't find an equivalent of keyset function for maps in C++ stl. Is it C++ really that poor.

  Read the article

• Regular expressions in c++ STL

  - by Radek Šimko

  Is there any native library in STL which is tested and works without any extra compiler options? I tried to use <regex>, but the compiler outputs this: In file included from /usr/include/c++/4.3/regex:40, from main.cpp:5: /usr/include/c++/4.3/c++0x_warning.h:36:2: error: #error This file requires compiler and library support for the upcoming ISO C++ standard, C++0x. This support is currently experimental, and must be enabled with the -std=c++0x or -std=gnu++0x compiler options.

  Read the article

• Memory Allocation by STL C++ Objects

  - by Vaibhav

  I am using malloc_stats() function to display the amount of "system bytes" and "in use" bytes used by the process. I wanted to know if the in use bytes also include the memory used by STL C++ Objects like map, vector, sets? If yes, is it safe to assume that this is only amount of memory that will be used by the process?

  Read the article

• C++ stl collections or linked lists

  - by Lucas

  I'm developing a OpenGL based simulation in C++. I'm optmizing my code now and i see throughout the code the frequently use of std:list and std:vector. What is the more performatic: to continue using C++ stl data structs or a pointer based linked list? The main operation that involve std::list and std::vector is open a iterator and loop through all items in the data structs and apply some processing

  Read the article

• C++ hash table w/o using STL

  - by Bobby

  I need to create a hash table that has a key as a string, and value as an int. I cannot use STL containers on my target. Is there a suitable hash table class for this purpose?

  Read the article

< Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >