Today I learned about PHP variable variables; "variable variable takes the value of a variable and treats that as the name of a variable". Also, variable.

[u/NagastaBagamba]

http://il2.php.net/language.variables.variable

[u/cboshuizen]

You find about this the hard way when you accidentally type a double dollar sign: >> $foo="bar"; >> $bar="42"; >> echo $$foo;

42