note 127568 added to language.variables.variable

In addition, it is possible to use associative array to secure name of variables available to be used within a function (or class / not tested). This way the variable variable feature is useful to validate variables; define, output and manage only within the function that receives as parameter an associative array : array('index'=>'value','index'=>'value'); index = reference to variable to be used within function value = name of the variable to be used within function <?php $vars = ['id'=>'user_id','email'=>'user_email']; validateVarsFunction($vars); function validateVarsFunction($vars){ //$vars['id']=34; <- does not work // define allowed variables $user_id=21; $user_email='email@mail.com'; echo $vars['id']; // prints name of variable: user_id echo ${$vars['id']}; // prints 21 echo 'Email: '.${$vars['email']}; // print email@mail.com // we don't have the name of the variables before declaring them inside the function } ?> ---- Server IP: 45.112.84.4 Probable Submitter: 185.85.3.173 (proxied: 181.4.163.106) ---- Manual Page -- https://php.net/manual/en/language.variables.variable.php Edit -- https://main.php.net/note/edit/127568 Del: integrated -- https://main.php.net/note/delete/127568/integrated Del: useless -- https://main.php.net/note/delete/127568/useless Del: bad code -- https://main.php.net/note/delete/127568/bad+code Del: spam -- https://main.php.net/note/delete/127568/spam Del: non-english -- https://main.php.net/note/delete/127568/non-english Del: in docs -- https://main.php.net/note/delete/127568/in+docs Del: other reasons-- https://main.php.net/note/delete/127568 Reject -- https://main.php.net/note/reject/127568 Search -- https://main.php.net/manage/user-notes.php