Question

PHP as declared refusing the use of reference variable (E_DEPRECATED in 5.3, E_STRICT in 5.4).
Initially, I thought it was the use of & in all the cases, but it seems not.

So I was wondering, what kind of code using reference is still allowed, and what now throws a E_DEPRECATED/STRICT error?

Answer 1

So far and from what I learned, here’s the result :

function foo(&$somevar) { /* ... */ }    // Allowed : pass-by-reference
function &foo($somevar) { /* ... */ }    // Allowed : returning-by-reference
$somevar = &othervar; *1                // Allowed

foo(&$somevar);                          // Refused : call-time pass-by-reference
$somevar = & new SomeObject();           // Refused
$somevar = & SomeObject::foo(); *2      // Refused

1. with $othervar being everything else than an object
2. With SomeObject::foo() returning a new instance of an object.