javascript - Is there an interest to use double boolean negation? -


as beginner in javascript, have question may seem bit weird. using external lib found on web in found code below :

if('useholes' in c){    this.config.useholes = !!c.useholes; }

is there interest use double exclamation mark or clumsy code ?

couldn't find answer yet guess can remove them wanted 100% sure.

with double ! force object return "boolean-able", if null or else, can evaluated bool true or false.


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