Using Variable Variables works fine inside functions for global
defined variables if you declare them as global inside the function.
Suprinsingly, it does not seem to work with superglobals. Take the
following example:
// code ////////////////////////////////////////////////////////////
<?php
$glob_var="Var 1";
$var_glob_var="glob_var";
$var_ENV="_ENV";
echo $_ENV["OS"],"\n";
echo $glob_var,"\n\n";
echo $var_glob_var,"\n";
echo $var_ENV,"\n\n";
echo $$var_glob_var,"\n";
echo ${$var_ENV}["OS"],"\n\n";
foo1($var_glob_var);
foo2($var_glob_var);
foo3();
foo4();
foo5($var_ENV);
foo6($var_ENV);
foo7();
foo8();
foo9();
function foo1($arg){
echo "--- In foo1 --------------\n";
echo $arg,"\n";
echo $$arg,"\n";
echo "--------------------------\n";
}
function foo2($arg){
global $glob_var;
echo "--- In foo2 --------------\n";
echo $arg,"\n";
echo $$arg,"\n";
echo "--------------------------\n";
}
function foo3(){
$arg="glob_var";
echo "--- In foo3 --------------\n";
echo $arg,"\n";
echo $$arg,"\n";
echo "--------------------------\n";
}
function foo4(){
global $glob_var;
$arg="glob_var";
echo "--- In foo4 --------------\n";
echo $arg,"\n";
echo $$arg,"\n";
echo "--------------------------\n";
}
function foo5($arg){
echo "--- In foo5 --------------\n";
echo $arg,"\n";
echo ${$arg}["OS"],"\n";
echo "--------------------------\n";
}
function foo6($arg){
global $_ENV;
echo "--- In foo6 --------------\n";
echo $arg,"\n";
echo ${$arg}["OS"],"\n";
echo "--------------------------\n";
}
function foo7(){
$arg="_ENV";
echo "--- In foo7 --------------\n";
echo $arg,"\n";
echo ${$arg}["OS"],"\n";
echo "--------------------------\n";
}
function foo8(){
global $_ENV;
$arg="_ENV";
echo "--- In foo8 --------------\n";
echo $arg,"\n";
echo ${$arg}["OS"],"\n";
echo "--------------------------\n";
}
function foo9(){
echo "--- In foo9 --------------\n";
echo $_ENV["OS"],"\n";
echo "--------------------------\n";
}
?>
// Output /////////////////////////////////////////////////////////
Windows_NT
Var 1
glob_var
_ENV
Var 1
Windows_NT
--- In foo1 --------------
glob_var
--------------------------
--- In foo2 --------------
glob_var
Var 1
--------------------------
--- In foo3 --------------
glob_var
--------------------------
--- In foo4 --------------
glob_var
Var 1
--------------------------
--- In foo5 --------------
_ENV
--------------------------
--- In foo6 --------------
_ENV
--------------------------
--- In foo7 --------------
_ENV
--------------------------
--- In foo8 --------------
_ENV
--------------------------
--- In foo9 --------------
Windows_NT
--------------------------
// Version //////////////////////////////////////////////
PHP 4.3.7 (cgi-fcgi) (built: Jun 2 2004 15:49:31)
Copyright (c) 1997-2004 The PHP Group
Zend Engine v1.3.0, Copyright (c) 1998-2004 Zend Technologies
// End //////////////////////////////////////////////////
I'm doing something wrong? Or this is the expected behavior? I know
I could use php references, but linking style does confuse me a bit (
how do you change a reference to point to a new variable if it's
allready referencing another one ? )
Thank you in advance
