How Does the \'this\' Pointer Resolve in Nested JavaScript Functions?

"this" Pointer Behavior in Nested JavaScript Functions

This question relates to understanding how the "this" pointer behaves when working with nested functions in JavaScript. When nesting functions, it's important to consider how the "this" pointer is resolved within each scope.

In the sample code provided, a "this" pointer is found in the nested function "doSomeEffects()" when called within the "displayMe()" function of the "std_obj" object. However, surprisingly, the "this" pointer refers to the "window" object and not the "std_obj" as expected.

This occurs because JavaScript's "this" pointer is dynamically bound to the calling context, which is not statically determined by the function's declaration. Instead, the "this" value is determined at the time the function is called.

When the nested function is invoked, the "this" pointer is not explicitly set, and JavaScript's default behavior takes over. By default, the "this" pointer will refer to the global "window" object when called without an explicit context.

To resolve this issue, we need to explicitly set the context for the nested function. This can be achieved by using either the "call()" or "apply()" methods. By calling "doSomeEffects.call(this)", we can manually bind the "this" pointer to the "std_obj" object.

Once the "this" pointer is explicitly set, nested functions can access the properties of the calling object correctly. In this case, the "this" pointer in "doSomeEffects" will refer to the "std_obj" object, allowing the nested function to work as intended.

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