Help! When declaring a function, the function name is preceded by an ampersand ???

Help! When declaring a function, the function name is preceded by an ampersand ??? This post was last edited by zx11307 at 17:57:24 on

As described in:
For example

Function & ret_ref () {$ var = "php"; return $ var ;}$ v = & ret_ref ();

What is the difference between "with" and "Without" in front of a function? Why add one &

Reply to discussion (solution)

Indicates that a reference can be returned.
However, this example cannot be shown.

Function & ret_ref () {static $ var; if (empty ($ var) $ var = "php"; return $ var ;}$ v = & ret_ref (); echo $ v; // php $ v = 'aaa'; echo ret_ref (); // aaa