Space After NOT operator

Exactly one space is allowed after the NOT operator.

Valid: A NOT operator followed by one space.

if (!<em> </em>$someVar || !<em> </em>$x instanceOf stdClass) {};

Invalid: A NOT operator not followed by whitespace.

if (!<em></em>$someVar || !<em></em>$x instanceOf stdClass) {};

Invalid: A NOT operator followed by a new line or more than one space.

if (!<em> </em>$someVar || !<em> </em>$x instanceOf stdClass) {};