I never knew it was possible to love a syntax but since, I fell in love with the self-invoking function which can be summarized like this : (function(){})(). Yes this is a valid syntax though it doesn't do much in this form (it creates a function that does nothing and call it).

Some people call it self-invocation or self-executing but I don't think it has an official name.

Let’s break it down

It will become clearer if I execute some code and write it on more than one line :

    function() {
      console.log("this line is called");

Line 1 : ( This first parenthesis is used as grouping operator. Read more here and here.

Line 2 : function() { This create an anonymous function. I could write something like function doSomething() { but in the case of a self-invoking function, this is useless because the function is in its own little scope (line 1) and can't be called from outside of it.

Line 3 : console.log(“this line is called”); This is the code that will be invoked.

Line 4 : } This clauses the function opened at line 2.

Line 5 : ) Clauses the parens opened at line 1.

Line 6 : (); We call the function created at line 2 and returned within the scope from line 1 to 4.

Let's write it in a more compact syntax :

(function() {
    console.log("this line is called");

See my post about using self-invoking functions to create namespaces.

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