empty Determine whether a variable is empty &reftitle.description; boolempty mixedvar Determine whether a variable is considered to be empty. A variable is considered empty if it does not exist or if its value equals &false;. empty does not generate a warning if the variable does not exist. &reftitle.parameters; var Variable to be checked No warning is generated if the variable does not exist. That means empty is essentially the concise equivalent to !isset($var) || $var == false. &reftitle.returnvalues; Returns &true; if var does not exist or has a value that is empty or equal to zero, aka falsey, see conversion to boolean. Otherwise returns &false;. &reftitle.examples; ]]> ]]> &example.outputs; &reftitle.notes; ¬e.language-construct; When using empty on inaccessible object properties, the __isset() overloading method will be called, if declared. &reftitle.seealso; isset __isset() unset array_key_exists count strlen The type comparison tables