Beware JavaScript's Boolean() Function

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I recently wrote the following line of code:

newsletterPopupEnabled = Boolean($("#newsletterPopupEnabled").val());

The point of this was to correctly parse a string of "true" or "false", as well as to take into account an empty string (which I expected to be interpreted as false).

I was very wrong.

The Boolean() function does not parse a string, but simply tests the truthiness of the parameter passed to it. So, a string of "false" is interpreted as truthy because the string is not null.

I now go to ponder the true meaning of "truth"... :)

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