From &#167; 3.6.3 of the C++03 standard:

&gt;Destructors (12.4) for initialized objects of static storage duration (declared at block scope or at namespace scope) are called as a result of returning from main and as a result of calling exit (18.3). These objects are destroyed in the reverse order of the completion of their constructor or of the completion of their dynamic initialization. If an object is initialized statically, the object is destroyed in the same order as if the object was dynamically initialized. For an object of array or class type, all subobjects of that object are destroyed before any local object with static storage duration initialized during the construction of the sub- objects is destroyed.

Furthermore, &#167; 9.4.2 7 states:

&gt;Static data members are initialized and destroyed exactly like non-local objects (3.6.2, 3.6.3).

However, if a destructor has no observable behavior, it may not be invoked. Terry Mahaffey details this in his [answer to &quot;Is a C++ destructor guaranteed not to be called until the end of the block?&quot;][1] .


  [1]: https://stackoverflow.com/questions/2087600/is-a-c-destructor-guaranteed-not-to-be-called-until-the-end-of-the-block/2088114#2088114

Somewhere after &quot;main&quot;

(you can&#39;t know or rely on the exact order in which they are called)

Is this the correct use of `Blockquote`,  `q` and `cite`?

    &lt;p&gt;
    &lt;blockquote&gt;Type HTML in the textarea above, &lt;q&gt;and it will magically appear&lt;/q&gt; in the frame below.
    &lt;/blockquote&gt;
    &lt;cite&gt;&lt;a href=&quot;http://stackoverflow.com&quot;&gt;refrence url&lt;/a&gt;
    &lt;/p&gt;

Is use of `Blockquote`,  `q` semantically correct? or both are presentational element , so should not be used?

Correct use of Blockquote, q and cite?

How can I get the element before the last element from an array in PHP5 ?

PHP - How to get the element before the last element from an array?

From my example program, it looks like it does call the destructors in both the cases. At what point does it call the destructors for global and class-static variables since they should be allocated in the data section of the program stack?

Does C++ call destructors for global and class static variables?

<p>From my example program, it looks like it does call the destructors in both the cases. At what point does it call the destructors for global and class-static variables since they should be allocated in the data section of the program stack?</p>


I understand that `reinterpret_cast` is dangerous, I&#39;m just doing this to test it. I have the following code:

	int x = 0;
	double y = reinterpret_cast&lt;double&gt;(x);


When I try to compile the program, it gives me an error saying

&gt; invalid cast from type &#39;float&#39; to type &#39;double

What&#39;s going on? I thought `reinterpret_cast` was the rogue cast that you could use to convert apples to submarines, why won&#39;t this simple cast compile?

Why doesn&#39;t this reinterpret_cast compile?

Let v1 be the target vector, v2 needs to be appended to the back of it.

I&#39;m now doing:

    v1.reserve(v1.size() + v2.size()); 
    copy(v2.begin(), v2.end(), back_inserter(v1));

Is this the most efficient way? Or can it maybe be done just via copying a chunk of memory?
Thanks!

What is the most efficient way to append one std::vector to the end of another?

I noticed in Effective STL that 


&gt; vector is the type of sequence that
&gt; should be used by default.

What&#39;s does it mean? It seems that ignore the efficiency `vector` can do anything. 

Could anybody offer me a scenario where `vector` is not a feasible option but `list` must be used?

vector vs. list in STL

So I&#39;ve got a library I&#39;m compiling and I need to link different third party things in depending on if it&#39;s the debug or release build (specifically the release or debug versions of those libraries).  Is there an easy way to do this in Cmake?

Edit: I should note I&#39;m using visual studio

Linking different libraries for Debug and Release builds in Cmake on windows?

I have a class implemented in C++ that&#39;s responsible for the arithmetic computation of the program, and an interface using WPF. I process the input with C# but then how can I use my C++ class?

I&#39;ve seen some comments about making a managed C++ wrapper class to interact with it, but I don&#39;t know where to start. Nor do I know how I&#39;d go to compile it along with all the other code. I can&#39;t really find a tutorial on this, and the stuff google shows on managed C++ doesn&#39;t really seem helpful.

Anything out there to help me out? This doesn&#39;t seem unreasonable to me.

**EDIT** Tried m3rLinEz solution but it&#39;s giving me a BadImageFormatException, I think it&#39;s because the DLL isn&#39;t generated. I did everything as told, I don&#39;t know what happened. Any ideas?

How do I call C++/CLI from C#?

I&#39;ve read all over the place that [global variables are bad][1] and alternatives should be used. In Javascript specifically, what solution should I choose.

I&#39;m thinking of a function, that when fed two arguments (&lt;code&gt;function globalVariables(Variable,Value)&lt;/code&gt;) looks if Variable exists in a local array and if it does set it&#39;s value to &lt;code&gt;Value&lt;/code&gt;, else, &lt;code&gt;Variable&lt;/code&gt; and &lt;code&gt;Value&lt;/code&gt; are appended. If the function is called without arguments (&lt;code&gt;function globalVariables()&lt;/code&gt;) it returns the array. Perhaps if the function is fired with just one argument (&lt;code&gt;function globalVariables(Variable)&lt;/code&gt;) it returns the value of &lt;code&gt;Variable&lt;/code&gt; in the array.

What do you think? I&#39;d like to hear your alternative solutions and arguments for using global variables.

&lt;h1&gt;How you would use &lt;code&gt;globalVariables();&lt;/code&gt;&lt;/h1&gt;
    function append(){
        globalVariables(&quot;variable1&quot;,&quot;value1&quot;); //globalVariables() would append variable1 to it&#39;s local array.
    };

    function retrieve(){
        var localVariable1 = globalVariables(&quot;variable1&quot;); //globalVariables() would return &quot;value1&quot;.
    };

    function retrieveAll(){
        var localVariable1 = globalVariables(); //globalVariables() would return the globalVariable()&#39;s entire, local [persistently stored between calls] array.
    };

    function set(){
        globalVariables(&quot;variable1&quot;,&quot;value2&quot;); //globalVariables() would set variable1 to &quot;value2&quot;.
    };

**Is this a [Singleton Pattern][2] BTW?**

In this specific scenario a function may set a variable at one point in time, and much later another function, maybe when a user submits a form, will need to get that variable. Therefore the first function couldn&#39;t pass the variable as an argument to the later function as it would never be called from the first.

Thank you, I appreciate all your help!


  [1]: http://c2.com/cgi/wiki?GlobalVariablesAreBad
  [2]: http://c2.com/cgi/wiki?SingletonPattern

I&#39;ve Heard Global Variables Are Bad, What Alternative Solution Should I Use?

I wrote the following code:

    Function find_results_idle()
    
        Public iRaw As Integer
        Public iColumn As Integer
        iRaw = 1
        iColumn = 1

And I get the error message:

&gt; &quot;invalid attribute in Sub or Function&quot;

Do you know what I did wrong?

I tried to use `Global` instead of `Public`, but got the same problem.

I tried to declare the function itself as `Public, but that also did no good.

What do I need to do to create the global variable?

How do I declare a global variable in VBA?

Currently I am working on a legacy web page that uses a ton of JavaScript, jQuery, Microsoft client JavaScript, and other libraries. The bottom line - I cannot rewrite the entire page from scratch as the business cannot justify it.  So... it is what it is. Anyway, I need to pollute (I really tried not too) the global namespace with a variable. There are the three options I was thinking about -

1. Just store/retrieve it using a normal JavaScript declaration - `var x = 0;`

2. Use jQuery to store/retrieve the value in a DOM tag - `$(&quot;body&quot;).data(&quot;x&quot;, 0);`

3. Use a hidden form field, and set/retrieve the value with jQuery - `$(&quot;whatever&quot;).data(&quot;x&quot;, 0);`

Is there a better way? I looked at the existing pile of code, and I do not believe the variable can be scoped in a function.


How to store a global value (not necessarily a global variable) in jQuery?

A bunch of my JavaScript code is in an external file called helpers.js. Inside the HTML that calls this JavaScript code I find myself in need of knowing if a certain function from helpers.js has been called.

I have attempted to create a global variable by defining:

    var myFunctionTag = true;

In global scope both in my HTML code and in helpers.js.

Heres what my html code looks like:

    &lt;html&gt;
    ...
    &lt;script type=&#39;text/javascript&#39; src=&#39;js/helpers.js&#39;&gt;&lt;/script&gt;	
    ...
    &lt;script&gt;
      var myFunctionTag = false;
      ...
      //I try to use myFunctionTag here but it is always false, even though it has been se t to &#39;true&#39; in helpers.js
    &lt;/script&gt;

Is what I am trying to do even feasible? 

Global variables in Javascript across multiple files

What do I pass as the first parameter &quot;`object`&quot; to the function `setattr(object, name, value)`, to set variables on the current module?

For example:

    setattr(object, &quot;SOME_CONSTANT&quot;, 42);

giving the same effect as:

    SOME_CONSTANT = 42

within the module containing these lines (with the correct `object`).

I&#39;m generate several values at the module level dynamically, and as I can&#39;t define `__getattr__` at the module level, this is my fallback.

How do I call setattr() on the current module?

    class MyDestructableClass {
       function __construct() {
           print &quot;\nIn constructor\n&quot;;
           $this-&gt;name = &quot;MyDestructableClass&quot;;
       }
    
       function __destruct() {
           print &quot;\nDestroying &quot; . $this-&gt;name . &quot;\n&quot;;
       }
    }
    
    $obj = new MyDestructableClass();


When the above script is in a **complex** environment,the `__destruct` won&#39;t get called when `exit`,but I can&#39;t reproduce it easily.Have someone ever noticed this ?

**EDIT**

I&#39;ll post the whole stuff here,it&#39;s the testing environment of symfony,which means you can easily reproduce it if you are familar with the framework:

    require_once dirname(__FILE__).&#39;/../bootstrap/Doctrine.php&#39;;
     
    
    $profiler = new Doctrine_Connection_Profiler();
    
    $conn = Doctrine_Manager::connection();
    $conn-&gt;setListener($profiler);
    
    $t = new lime_test(0, new lime_output_color());
    
    class MyDestructableClass {
       function __construct() {
           print &quot;\nIn constructor\n&quot;;
           $this-&gt;name = &quot;MyDestructableClass&quot;;
       }
    
       function __destruct() {
           print &quot;\nDestroying &quot; . $this-&gt;name . &quot;\n&quot;;
       }
    }
    
    $obj = new MyDestructableClass();
    $news = new News();
    
    $news-&gt;setUrl(&#39;http://test&#39;);
    $news-&gt;setHash(&#39;http://test&#39;);
    $news-&gt;setTitle(&#39;http://test&#39;);
    $news-&gt;setSummarize(&#39;http://test&#39;);
    $news-&gt;setAccountId(1);
    $news-&gt;setCategoryId(1);
    $news-&gt;setThumbnail(&#39;http://test&#39;);
    $news-&gt;setCreatedAt(date(&#39;Y-m-d H:i:s&#39;,time()));
    $news-&gt;setUpdatedAt(date(&#39;Y-m-d H:i:s&#39;,time()));
    $news-&gt;save();
    exit();

When will __destruct not be called in PHP?

When creating a new instance of a `MyClass` as an argument to a function like so:

    class MyClass
    {
      MyClass(int a);
    };    
    
    myFunction(MyClass(42));

Does the standard make any guarantees on the timing of the destructor?

Specifically, can I assume that it is going to be called before the next statement after the call to `myFunction()` ?


C++: Life span of temporary arguments?

Is this program well-defined, and if not, why exactly?

    #include &lt;iostream&gt;
    #include &lt;new&gt;
    struct X {
        int cnt;
        X (int i) : cnt(i) {}
        ~X() {  
                std::cout &lt;&lt; &quot;destructor called, cnt=&quot; &lt;&lt; cnt &lt;&lt; std::endl;
                if ( cnt-- &gt; 0 )
                    this-&gt;X::~X(); // explicit recursive call to dtor
        }
    };
    int main()
    {   
        char* buf = new char[sizeof(X)];
        X* p = new(buf) X(7);
        p-&gt;X::~X();  // explicit call to dtor
        delete[] buf;
    }

My reasoning: although [invoking a destructor twice is undefined behavior][1], per 12.4/14, what it says exactly is this:
&gt; the behavior is undefined if the
&gt; destructor is invoked for an object
&gt; whose lifetime has ended

Which does not seem to prohibit recursive calls. While the destructor for an object is executing, the object&#39;s lifetime has not yet ended, thus it&#39;s not UB to invoke the destructor again. On the other hand, 12.4/6 says:
&gt; After executing the body [...] a
&gt; destructor for class X calls the
&gt; destructors for X&#39;s direct members,
&gt; the destructors for X&#39;s direct base
&gt; classes [...]

which means that after the return from a recursive invocation of a destructor, all member and base class destructors will have been called, and calling them again when returning to the previous level of recursion would be UB. Therefore, a class with no base and only POD members can have a recursive destructor without UB. Am I right?

  [1]: https://stackoverflow.com/questions/2771567/why-exactly-is-calling-the-destructor-for-the-second-time-undefined-behavior-in-c


Can a destructor be recursive?

Consider the following code:

    void foo()
    {
        {
            CSomeClass bar;
     
            // Some code here...
    
            goto label;
            
            // and here...
        }
    
    label:
        // and here...
    }
    
Will the destructor of bar be called ?

Goto out of a block: do destructors get called?

Please give me some real life examples when you had to use __destruct in your classes.

Content Type	Original Author	Original Content on Stackoverflow
Question	user236215	View Question on Stackoverflow
Solution 1 - C++	outis	View Answer on Stackoverflow
Solution 2 - C++	Vi.	View Answer on Stackoverflow

Does C++ call destructors for global and class static variables?

C++ Problem Overview

C++ Solutions

Solution 1 - C++

Solution 2 - C++

PHP - How to get the element before the last element from an array?

Correct use of Blockquote, q and cite?

Attributions