1.2.865. Not Or Tilde

There are two NOT operator in PHP : ! and ~. The first is a logical operator, and returns a boolean. The second is a bit-wise operator, and flips each bit.

Although they are distinct operations, there are situations where they provide the same results. In particular, when processing booleans.

Yet, ! and ~ are not the same. ~ has a higher priority, and will not yield to instanceof, while ! does.

The analyzed code has less than 10% of one of them : for consistency reasons, it is recommended to make them all the same.

<?php

// be consistent
if (!$condition) {
    doSomething();
}

if (~$condition) {
    doSomething();
}

?>

See also Bitwise Operators, Logical Operators and Operators Precedences.

1.2.865.1. Connex PHP features

• logical-operator

• bitwise-operator

1.2.865.1.1. Suggestions

• Use the ! in logical expressions

• Use the ~ in bitwise expressions, with integers for example

1.2.865.1.2. Specs

Short name	Structures/NotOrNot
Rulesets	All, Preferences
Exakat since	1.8.9
PHP Version	All
Severity	Minor
Time To Fix	Quick (30 mins)
Precision	Very high
Available in	Entreprise Edition, Exakat Cloud