Returning References

Returning by reference is useful when you want to use a function
to find to which variable a reference should be bound. Do
 use return-by-reference to increase performance.
The engine will automatically optimize this on its own. Only return
references when you have a valid technical reason to do so. To
return references, use this syntax:

In this example, the property of the object returned by the
 function would be set, not the
copy, as it would be without using reference syntax.

not```php

value; } } $obj = new Foo(); $myValue = &$obj->getValue(); // $myValue is a reference to $obj->value, which is 42 $obj->value = 2; echo $myValue; // Prints the new value of $obj->value, i.e. 2 ?>


`getValue`

> **Opmerking:** > Unlike parameter passing, here you have to use
>       in both places - to indicate that you
>      want to return by reference, not a copy, and to indicate that
>      reference binding, rather than usual assignment, should be done
>      for .
>     `&amp;``$myValue`

> **Opmerking:** > If you try to return a reference from a function with the syntax:
>       this will 
>      work as you are attempting to return the result of an
>      , and not a variable, by reference. You can
>      only return variables by reference from a function - nothing else.
>     `return ($this-&gt;value);`*not**expression*


   To use the returned reference, you must use reference assignment:
    
   
   To pass the returned reference to another function expecting a reference
   you can use this syntax:
    
   ```php
<?php

function &collector()
{
    static $collection = array();
    return $collection;
}

$collection = &collector();
// Now the $collection is a referenced variable that references the static array inside the function

$collection[] = 'foo';

print_r(collector());
// Array
// (
//    [0] => foo
// )

?>

Opmerking: > If the assignment is done without the symbol, e.g. , the variable will receive a copy of the value, not the reference returned by the function. &``$collection = collector();``$collection

<?php

function &collector()
{
    static $collection = array();
    return $collection;
}

array_push(collector(), 'foo');

?>

Opmerking: > Note that will work, it results in a fatal error. array_push(&collector(), 'foo');not

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Returning References

Returning References

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