It tells NGen that it is OK to inline the method it&#39;s applied to even in a different assembly.

For example:

 - `String.Equals` has `[TargetedPatchingOptOut]`
 - You write a program that calls `String.Equals`
 - You run [NGen](http://msdn.microsoft.com/en-us/library/6t9t5wcf%28v=VS.100%29.aspx) on this program for maximum performance
 - NGen will inline the `String.Equals` call, replacing the method call instruction with the actual code in the method.  
Method calls are (slightly) expensive, so this is a performance boost for frequently-called methods.

However, if Microsoft finds a security hole in `String.Equals`, they cannot just update `mscorlib.dll`, because that won&#39;t affect the assembly that you just NGen&#39;d.  (Since it has raw machine code without referencing `String.Equals`).  
I assume that if that were to actually happen, the security update would clear the NGen store.

Note that this attribute is only useful in the .NET Framework assemblies. You don&#39;t need it in your own. You can find more information about that here: https://stackoverflow.com/a/14982340/631802

**(Note: This question is about not having to specify the number of elements and still allow nested types to be directly initialized.)**  
[This question][1] discusses the uses left for a C array like `int arr[20];`. On [his answer][2], @James Kanze shows one of the last strongholds of C arrays, it&#39;s unique initialization characteristics:

    int arr[] = { 1, 3, 3, 7, 0, 4, 2, 0, 3, 1, 4, 1, 5, 9 };
We don&#39;t have to specify the number of elements, hooray! Now iterate over it with the C++11 functions `std::begin` and `std::end` from `&lt;iterator&gt;` ([or your own variants][3]) and you never need to even think of its size.

Now, are there any (possibly TMP) ways to achieve the same with `std::array`? Use of macros allowed to make it look nicer. :)

    ??? std_array = { &quot;here&quot;, &quot;be&quot;, &quot;elements&quot; };
***
**Edit**: Intermediate version, compiled from various answers, looks like this:

    #include &lt;array&gt;
    #include &lt;utility&gt;
     
    template&lt;class T, class... Tail, class Elem = typename std::decay&lt;T&gt;::type&gt;
    std::array&lt;Elem,1+sizeof...(Tail)&gt; make_array(T&amp;&amp; head, Tail&amp;&amp;... values)
    {
      return { std::forward&lt;T&gt;(head), std::forward&lt;Tail&gt;(values)... };
    }

    // in code
    auto std_array = make_array(1,2,3,4,5);
And employs all kind of cool C++11 stuff:

* Variadic Templates
* `sizeof...`
* rvalue references
* perfect forwarding
* `std::array`, of course
* uniform initialization
* omitting the return type with uniform initialization
* type inference (`auto`)

And an example can be found [here][4].

**However**, as @Johannes points out in the comment on @Xaade&#39;s answer, you can&#39;t initialize nested types with such a function. Example:

    struct A{ int a; int b; };
    
    // C syntax
    A arr[] = { {1,2}, {3,4} };
    // using std::array
    ??? std_array = { {1,2}, {3,4} };
Also, the number of initializers is limited to the number of function and template arguments supported by the implementation.

  [1]: https://stackoverflow.com/questions/6111565/now-that-we-have-stdarray-what-uses-are-left-for-c-style-arrays
  [2]: https://stackoverflow.com/questions/6111565/now-that-we-have-stdarray-what-uses-are-left-for-c-style-arrays/6113104#6113104
  [3]: https://stackoverflow.com/questions/5897319/how-to-use-stdsort-to-sort-a-array-in-c/5897358#5897358
  [4]: http://ideone.com/fsfT0

How to emulate C array initialization &quot;int arr[] = { e1, e2, e3, ... }&quot; behaviour with std::array?

Imploding  a simple array 

would look like this

	$array = array(&#39;lastname&#39;, &#39;email&#39;, &#39;phone&#39;);
	$comma_separated = implode(&quot;,&quot;, $array);

and that would return this

     lastname,email,phone

great, so i might do this instead 

	$array = array(&#39;lastname&#39;, &#39;email&#39;, &#39;phone&#39;);
	$comma_separated = implode(&quot;&#39;,&#39;&quot;, $array);
	$comma_separated = &quot;&#39;&quot;.$comma_separated.&quot;&#39;&quot;;

and now i have what I want a nice pretty csv string 

     &#39;lastname&#39;,&#39;email&#39;,&#39;phone&#39;

is there a better way to do this, it feels to me like there should be an optional parameter for implode am I missing something ?



php implode (101) with quotes

Been going through some framework classes using reflector and noticed a number of the methods and properties have the following attribute 



    [TargetedPatchingOptOut(&quot;Performance critical to inline across NGen image boundaries&quot;)]



I&#39;m pretty sure I have also seen the above comment somewhere else and never followed it up. 

Could someone please tell me what this means in the C# and any other context?


TargetedPatchingOptOut: &quot;Performance critical to inline across NGen image boundaries&quot;?

Been going through some framework classes using reflector and noticed a number of the methods and properties have the following attribute
<pre><code class="hljs language-csharp">[TargetedPatchingOptOut("Performance critical to inline across NGen image boundaries")]
</code></pre>
I'm pretty sure I have also seen the above comment somewhere else and never followed it up.
Could someone please tell me what this means in the C# and any other context?

I am splitting a string based on whitespace as follows:

    string myStr = &quot;The quick brown fox jumps over the lazy dog&quot;;

    char[] whitespace = new char[] { &#39; &#39;, &#39;\t&#39; };
    string[] ssizes = myStr.Split(whitespace);

It&#39;s irksome to define the char[] array everywhere in my code I want to do this. Is there more efficent way that doesn&#39;t require the creation of the character array (which is prone to error if copied in different places)?

Best way to specify whitespace in a String.Split operation

I have a list of objects and I need to save that somewhere in my computer. I have read some forums and I know that the object has to be `Serializable`. But it would be nice if I can get an example. For example if I have the following:

    [Serializable]
    public class SomeClass
    {
         public string someProperty { get; set; }
    }

    SomeClass object1 = new SomeClass { someProperty = &quot;someString&quot; };
    
But how can I store `object1` somewhere in my computer and later retrieve?
    

How to save/restore serializable object to/from file?

I&#39;m trying to POST a `JsonObject` using `HttpClient` from Web API. I&#39;m not quite sure how to go about this and can&#39;t find much in the way of sample code. 

Here&#39;s what I have so far:

    var myObject = (dynamic)new JsonObject();
    myObject.Data = &quot;some data&quot;;
    myObject.Data2 = &quot;some more data&quot;;

    HttpClient httpClient = new HttpClient(&quot;myurl&quot;);
    httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue(&quot;application/json&quot;));

    HttpResponseMessage response = httpClient.Post(&quot;&quot;, ???);

I think I need to cast my `JsonObject` as a `StreamContent` but I&#39;m getting hung up on that step. 


POSTing JsonObject With HttpClient From Web API

I&#39;ve struck upon something I don&#39;t really understand.

I have a project, where I have an interface that is internal. The class that implements that interface is also internal. In the implementation of the interface, I make all the members that I implement, internal. I did not do an explicit implementation.

I have two interfaces and two classes that implement those interfaces where this works fine.

It would look something like this:

    internal interface IA
    {
        void X();
    }

and then

    internal class CA : IA
    {
        internal void X()
        {
            ...
        }
    }

This works fine for the two aforementioned classes. But when I try to do it with another interface and class, it doesn&#39;t work. In fact, for the example above, I get the error:

&#39;WindowsFormsApplication1.CA&#39; does not implement interface member &#39;WindowsFormsApplication1.IA.X()&#39;. &#39;WindowsFormsApplication1.CA.X()&#39; cannot implement an interface member because it is not public.

I realize I can make the methods public or do an explicit implementation (and omit the internal and public modifiers), but I&#39;m simply confused as to why it works with the two classes it works with and yet I seem to be unable to replicate it anywhere else.

Butchering the code a bit (because it&#39;s confidential), this is one of the ones that actually works in my project.

    internal interface IScanner
    {
        void SetHardware(Hardware hardware);
        void Start();
        void PauseScan();
        void ResumeScan();
        void Stop();
        bool InScan { get; }
        event ScanCompleteHandler ScanComplete;
    }

Then I have the class:

    internal class MyScanner : IScanner
    {
        internal void SetHardware(Hardware hardware)
        {
           ...
        }

        internal void Start()
        {
            ...
        }

        internal void Stop()
        {
            ...
        }

        internal void PauseScan()
        {
            ...
        }

        internal void ResumeScan()
        {
            ...
        }

        internal bool InScan
        {
            get
            {
                ...
            }
        }

        internal event ScanCompleteHandler ScanComplete;
    }

To make things even stranger, I created another internal class called Temp. I then had it implement the IScanner interface and I copied and pasted the implementation from MyScanner over to it and it won&#39;t compile, giving me the error that: &quot;cannot implement an interface member because it is not public.&quot;

Can anyone explain this inconsistency?

Thanks

(Updated to fix a typo and clarify some text)

**EDIT: Additional Information**

I ran the code through reflector and my implementations have been compiled as explicit implementations, even though they aren&#39;t explicit. Reflector shows no signs of the internal keywords. All I can guess is that this is some sort of glitch in the compiler that, for some reason, allowed me to make them internal and implicit and that it somehow resolved that as being an explicit implementation. 

I&#39;ve looked over the code a number of times. I can&#39;t find any other explanation for it.

C# internal interface with internal implementation

I need to remove time portion of date time or probably have the date in following format in `object` form not in the form of `string`.

    06/26/2009 00:00:00:000

I can not use any `string` conversion methods as I need the date in `object` form.

I tried first converting the `DateTime` to a `string`, remove the time specific date from it, but it adds `12:00:00 AM` as soon as I convert it back to `DateTime` `object` back again.

How to remove time portion of date in C# in DateTime object only?

How can I read a connection string from a `web.config` file into a public class contained within a class library?

I&#39;ve tried:

    WebConfigurationManager

    ConfigurationManager

But these classes are not recognized within my class library.

Read connection string from web.config

I read some C# article to combine a path using `Path.Combine`(part1,part2).

It uses the following:

    string part1 = @&quot;c:\temp&quot;;
    string part2 = @&quot;assembly.txt&quot;;

May I know what is the use of `@` in part1 and part2?


What does the @ prefix do on string literals in C#

Could you tell me what is the main differences between Style and ControlTemplate ?
When or why to use one or the other ?

To my eyes, they are exactly the very **same**. As I am beginner I think that I am wrong, thus my question.


Difference between Style and ControlTemplate

I found a similar question here:

https://stackoverflow.com/questions/1298255/how-do-i-suppress-script-errors-when-using-the-wpf-webbrowser-control

But non of those solutions work for me.  I need to stop the popups from appearing as i am using the WebBrowser to automate admin tasks on a website.

`SuppressScriptErrors` does not appear to be an available attribute on my WebControl :(

WPF WebBrowser control - how to suppress script errors?

Suppose I have a non-volatile int field, and a thread which `Interlocked.Increment`s it. Can another thread safely read this directly, or does the read also need to be interlocked?

I previously thought that I had to use an interlocked read to guarantee that I&#39;m seeing the current value, since, after all, the field isn&#39;t volatile. I&#39;ve been using `Interlocked.CompareExchange(int, 0, 0)` to achieve that.

However, I&#39;ve stumbled across [this answer](https://stackoverflow.com/questions/1186515/interlocked-and-volatile/1186562#1186562) which suggests that actually plain reads will always see the current version of an `Interlocked.Increment`ed value, and since int reading is already atomic, there&#39;s no need to do anything special. I&#39;ve also found [a request in which Microsoft rejects a request for Interlocked.Read(ref int)](http://connect.microsoft.com/VisualStudio/feedback/details/256490/interlocked-read-only-does-long-data-type), further suggesting that this is completely redundant.

So can I really safely read the most current value of such an `int` field without `Interlocked`?

How to correctly read an Interlocked.Increment&#39;ed int field?

Core is GHC&#39;s intermediate language. Reading Core can help you better understand the performance of your program. Someone asked me for documentation or tutorials on reading Core, but I couldn&#39;t find much.

What documentation is available for reading GHC Core?

Here&#39;s what I&#39;ve found so far:

* [Write Haskell as fast as C: exploiting strictness, laziness and recursion][1]
* [Haskell as fast as C: working at a high altitude for low level performance][2]
* [RWH: Chapter 25. Profiling and optimization][3]
* [High-Performance Haskell talk at CUFP][4] (slide 65-80)

  [1]: http://donsbot.wordpress.com/2008/05/06/write-haskell-as-fast-as-c-exploiting-strictness-laziness-and-recursion/
  [2]: http://donsbot.wordpress.com/2008/06/04/haskell-as-fast-as-c-working-at-a-high-altitude-for-low-level-performance/
  [3]: http://book.realworldhaskell.org/read/profiling-and-optimization.html
  [4]: http://blog.johantibell.com/2010/09/slides-from-my-high-performance-haskell.html


Reading GHC Core

A fairly simple question... Compilers these days tend to do a significant amount of optimizations. Do they also remove unused functions from the final output? 

Do unused functions get optimized out?

I want to learn how to write a lexer. My university course had an assignment where we had to write a parser (and a lexer to go along with it) but this was given to us with no instruction or feedback (beyond the mark) so I didn&#39;t really learn much from it.

After searching for this topic, I can only find fairly advanced write ups which focus on areas which I feel are a few steps ahead of where I am at. I want a discussion on the basics of writing a lexer for a very simple language which I can use as a basis for investigating tokenising more complex languages.

At this stage I&#39;m not really interested in best practices or optimisation techniques but instead prefer a focus on the essentials. What are some good resources to get me started?

Where can I learn the basics of writing a lexer?

How does the compilation and linking process work?  

_&lt;sub&gt;
(Note: This is meant to be an entry to [Stack Overflow&#39;s C++ FAQ](https://stackoverflow.com/questions/tagged/c++-faq). If you want to critique the idea of providing an FAQ in this form, then [the posting on meta that started all this](https://meta.stackexchange.com/questions/68647/setting-up-a-faq-for-the-c-tag) would be the place to do that. Answers to that question are monitored in the [C++ chatroom](https://chat.stackoverflow.com/rooms/10/c-lounge), where the FAQ idea started out in the first place, so your answer is very likely to get read by those who came up with the idea.)
&lt;/sub&gt;_

How does the compilation/linking process work?

I am not an expert, so go easy on me.  Are there any differences between these two code segments?

    #define BIT3 (0x1
    &lt;
    &lt;
    3)
    static int a;

and

    #define BIT3 (0x1 &lt;&lt; 3) static int a;

Also, is there a way to write the first in one line?  What is the point of this multi-line style?  Is the following code good?

    #define BIT3 (0x1 &lt;&lt; 3)
    static int a;

Content Type	Original Author	Original Content on Stackoverflow
Question	Maxim Gershkovich	View Question on Stackoverflow
Solution 1 - C#	SLaks	View Answer on Stackoverflow

TargetedPatchingOptOut: "Performance critical to inline across NGen image boundaries"?

C# Problem Overview

C# Solutions

Solution 1 - C#

php implode (101) with quotes

How to emulate C array initialization "int arr[] = { e1, e2, e3, ... }" behaviour with std::array?

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