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JavaScript

Posted by Laurence kite
Laurence kite
11,768 Points

Modules in JavaScript

I am confused as to why a function definition is placed within a round brackets.?

(function () { // code })();

why is this different from

function() { //code } ();

1 Answer

Steven Parker
Steven Parker
243,656 Points
Steven Parker
Steven Parker
243,656 Points

The parentheses ("round brackets") make the function declaration into an expression.

The expression represents the newly-declared function and allow it to be invoked using the other parentheses at the end.

You can skip the enclosing parentheses if there is something else (like a math operator or an assignment) that would make the declaration into an expression.

Also see my answer to your other question.