While looking at various JavaScript libraries, I have noticed a relatively common practice of passing either the window or the document object as part of the arguments given to the library initialization function.
Examples:
- DOM4
- ContentLoaded
- EasyXDM
- fingerprintjs
While I understand very well why that would be done for libraries that are designed to run on non-browser environments, I do not know why that is done for libraries that seem designed only for client browser environments. (Such as all the examples given above).
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It also helps to speed up the library as window or document is now locally bound. And this also ensures that if latter the user, replaces the window object with say: window = "Help, I'm trapped in a window overwriting assignment statement.";; the library continues to work.
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