How does PHP handle the assignment of a variable by reference when the original variable is unset?

Question

PHP Intermediate — Hard

How does PHP handle the assignment of a variable by reference when the original variable is unset?

Accepted Answer

In PHP, unsetting a variable only destroys the variable name binding. If a variable is referenced, the underlying data structure remains in memory as long as at least one reference exists. Unsetting one variable name does not affect the value held by other references.