I'm studying closures and the global scope, and am confused about when to use }()) vs. })(). It seems that I've lucked upon a situation where it doesn't matter which one I use.
(function() {
var myFunction = 开发者_JAVA百科(function() {
var i=100;
return function() {
return i++;
}
}());
var X = myFunction();
console.log(X);
X = myFunction();
console.log(X);
})();
Its how expressions work in JS.
The following all work because the +
,-
,(
,~
... designate the beginning of an expression.
!function(){}()
~function(){}()
+function(){}()
-function(){}()
(function(){})()
(function(){}())
(function () { return 1; });
doesn't evaluate the function. ("append" + " us")
does evaluate the strings.
So yeah, in this case it doesn't matter because:
var myFunction = (function() {
var i=100;
return function() {
return i++;
}
}());
evaluates to (function() { return i++; }
which just returns the anonymous function.
and:
var myFunction = (function() {
var i=100;
return function() {
return i++;
}
})();
evaluates myFunction after the braces. And.. just returns the anonymous function. Woh.
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