What's the purpose of javascript parameters that are overwritten in the function? -


i have code snippet include in project, , i'd know if there's purpose why written or if should clean up. there optimization trick don't know about?

here's (sanitized) code snippet. notice a,b,c,d passed in , assigned in function.

(function (a, b, c, d) {     = '//url/to/js/file.js';     b = document; c = 'script'; d = b.createelement(c); d.src = a; d.type = 'text/java' + c; d.async = true;     = b.getelementsbytagname(c)[0]; a.parentnode.insertbefore(d, a); })();

i found this answer after writing question up. reason?

that way can make local scoped variable without explicitly declaring using var statement.

iirc it's commonly used code minifiers.


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