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Order between destruction of global object and atexit in C++

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问题 I wonder that can sure order between destruction of global object and atexit in C++ I have a global object and register atexit function like below: static MyClass g_class; void onExit() { // do some destruction } int main() { atexit(onExit); return 0; } I've found onExit() is invoked before MyClass::~MyClass() in Visual Studio 2012 and gcc4.7.2. Am I sure that onExit is always invoked before global object(like g_class ) destruction? I wonder global object register order and atexit register

ReferenceError and the global object

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问题 In javascript window is the global object, which means every object in the global scope is a child of window . So why I get this result: console.log(window.foo); // No error, logs "undefined". console.log(foo); // Uncaught ReferenceError: foo is not defined. Fiddle Those two lines should be the same, shouldn't they? 回答1: Because with window.foo you are explicitly looking for foo property of window object which is not the case in latter option. In the latter option, if foo isn't defined, you

Check if a global property/function has been overwritten in JavaScript

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问题 JavaScript makes it easy to overwrite properties and functions of the global object. I'd like to find a way to check if the original version of a global property has been replaced. Consider someone putting this in their HTML: <script type="text/javascript"> window.encodeURIComponent = eval; </script> <script type="text/javascript" src="myscript.js"></script> If myscript.js calls the encodeURIComponent function somewhere, it will now behave unpredictably. So is there a way I can check inside

ReferenceError and the global object

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In javascript window is the global object, which means every object in the global scope is a child of window . So why I get this result: console.log(window.foo); // No error, logs "undefined". console.log(foo); // Uncaught ReferenceError: foo is not defined. Fiddle Those two lines should be the same, shouldn't they? Because with window.foo you are explicitly looking for foo property of window object which is not the case in latter option. In the latter option, if foo isn't defined, you should as developer be able to know that it isn't defined and get the clear error warning rather than