Geek asks and answers

Are strings bound to PHP5?

Are references or copied strings passed as arguments or assigned to variables used in PHP5?

+3
source share
2 answers

The function can help you answer this question. debug_zval_dump()


For example, if I ran the following code:

$str = 'test';
debug_zval_dump($str);      // string(4) "test" refcount(2)

my_function($str);
debug_zval_dump($str);      // string(4) "test" refcount(2)

function my_function($a) {
    debug_zval_dump($a);    // string(4) "test" refcount(4)
    $plop = $a . 'glop';
    debug_zval_dump($a);    // string(4) "test" refcount(4)
    $a = 'boom';
    debug_zval_dump($a);    // string(4) "boom" refcount(2)
}

I get the following output:

string(4) "test" refcount(2)
string(4) "test" refcount(4)
string(4) "test" refcount(4)
string(4) "boom" refcount(2)
string(4) "test" refcount(2)


So, I would say:

  • "Refcounted" strings when passed to functions (and possibly when assigned to variables)
  • BUT do not forget that PHP makes a copy when writing


For more information, here are some links that may be helpful:

+7

.

+1

More articles:


All Articles