Why Does JavaScript Function Aliasing Fail with `document.getElementById` in Firefox, Chrome, and Debug Windows?

JavaScript Function Aliasing Conundrum

While attempting to use the alias method for aliasing JavaScript functions, some users have encountered roadblocks in Firefox, Chrome, and even Google Chrome's debug windows.

The Cause

Upon analysis, it was discovered that JavaScript functions are loosely connected to their host objects. When calling a function, JavaScript determines the scope and passes it to the function. In the case of aliasing, the scope is not explicitly specified, so the global Window object is passed as the scope.

Impact on Document.getElementById Aliasing

With document.getElementById specifically, this misalignment becomes problematic because getElementById expects the this object to be the document object. When the aliased function is called without specifying the correct scope (i.e., document), the function call fails, causing the error "Illegal operation on WrappedNative prototype object".

Working Solution

To resolve this issue, the apply method can be used to manually specify the scope upon function invocation. For example, instead of calling myAlias directly, the following syntax can be used:

myAlias.apply(document, ['someElement']);

Exception: Internet Explorer

Notably, function aliasing does work as expected in Internet Explorer. This is likely due to Internet Explorer's implementation of getElementById, which may equate the window object with the document object.

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