note 129738 added to language.variables.variable

You can use illegal variable names with variable variables. <?php $a = "a"; $$a = "A"; $b = "\$a"; echo $$b; // Warning: Undefined variable $$a in code.php on line 7 $$b = "A!"; echo "$b: ".$$b; // $a: A! $null = "0"; $$null = "echo"; echo "$null: ".$$null; // 0: echo ?> Those two variables can only be accessed via variable variables. $0 and $\$a are both illegal variables. ---- Server IP: 45.112.84.4 Probable Submitter: 80.90.5.137 (proxied: 85.22.155.34) ---- Manual Page -- https://php.net/manual/en/language.variables.variable.php Edit -- https://main.php.net/note/edit/129738 Del: integrated -- https://main.php.net/note/delete/129738/integrated Del: useless -- https://main.php.net/note/delete/129738/useless Del: bad code -- https://main.php.net/note/delete/129738/bad+code Del: spam -- https://main.php.net/note/delete/129738/spam Del: non-english -- https://main.php.net/note/delete/129738/non-english Del: in docs -- https://main.php.net/note/delete/129738/in+docs Del: other reasons-- https://main.php.net/note/delete/129738 Reject -- https://main.php.net/note/reject/129738 Search -- https://main.php.net/manage/user-notes.php