Is there any difference between !!$var and (bool) $var?

Question

Is there any differences between using !! or (bool) operators when you want to cast data types?

    $number = 1;

    var_dump( (bool) $number ) //true
    var_dump( !! $number ) //true

Answer 1

(bool), as mentioned by meagar in the comments, is more semantically meaningful. Also, keep in mind that (bool) is performing one operation, while !! is performing two (a double-negation). The difference in performance is pretty much undetectable, but it may add up if used in bulk.