NULL
The null type is PHP's unit type, i.e. it has only one value: null
.
Undefined, and unset() variables will resolve to the value null
.
Syntax
There is only one value of type null, and that is the case-insensitive constant null
.
Casting to null
WarningThis feature has been DEPRECATED as of PHP 7.2.0, and REMOVED as of PHP 8.0.0. Relying on this feature is highly discouraged.
Casting a variable to null using (unset) $var
will not remove the variable or unset its value. It will only return a null
value.