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POWhat is so special about closures?
 

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    <p>I've been <a href="http://www.devsource.com/c/a/Languages/Cigars-Lambda-Expressions-and-NET/1/" rel="nofollow noreferrer">reading this article about closures</a> in which they say:</p> <ul> <li>"all the plumbing is automatic"</li> <li>the compiler "creates a wrapper class" and "extends the life of the variables"</li> <li>"you can use local variables without worry"</li> <li>the .NET compiler takes care of the plumbing for you, etc.</li> </ul> <p>So I made an example based on their code and to me, it seems as though closures just act similarly to regular named methods which also "take care of the local variables without worry" and in which "all the plumbing is automatic". </p> <p><strong>Or what problem did this "wrapping of local variables" solve that makes closures so special / interesting / useful?</strong></p> <pre><code>using System; namespace TestingLambda2872 { class Program { static void Main(string[] args) { Func&lt;int, int&gt; AddToIt = AddToItClosure(); Console.WriteLine("the result is {0}", AddToIt(3)); //returns 30 Console.ReadLine(); } public static Func&lt;int, int&gt; AddToItClosure() { int a = 27; Func&lt;int, int&gt; func = s =&gt; s + a; return func; } } } </code></pre> <h1>Answer</h1> <p>So the answer to this one is to read <a href="http://csharpindepth.com/Articles/Chapter5/Closures.aspx" rel="nofollow noreferrer">Jon Skeet's article on closures</a> that Marc pointed out. This article not only shows the evolution leading up to lambda expressions in C# but also shows how closures are dealt with in Java, an excellent read for this topic.</p>
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    1. USEdward Tanguay
    1. USEdward Tanguay
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      1. USManrico Corazzi
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    1. COOther languages (such as Javascript) support closures. Are you asking about the concept or C#'s specific implementation?
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    2. COI think that example is too simple to understand the power of closures.
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      1. USNuno Furtado
    3. CO@strager: I mean the concept in general, I'm trying to get my head around delegates, closures, maps, lambdas, "lambda expressions", "lambda trees", anonymous functions, currying, etc. and in general the new paradigms of functional programming which seem to extend beyond any one language, have their roots in mathematics, etc. (I had put C# in the title because Stackoverflow now tells you that your title it "not good enough, add unique words"...)
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