PHP's For-each / for behaviour – Value remains accesible after Foreach ends

I have this piece of code:

$exists = false;
foreach ($outsiderTests as $key => $outsiderTest) {
   $textExists = null;
   foreach ($tests as $test) {
       if ($outsiderTest->getName() == $test->getName()) {
           $exists = true;
           $existingTest = $test;
           break;
       } else
           $exists = false;
   }

   var_dump($existingTest, $test);
}

As you can see, I want to see if there is an equivalent to an outsiderTest in $tests array. I thought I would have to save the existing equivalent $test on another variable as it would be gone after the foreach ends, but it does not.

The value of $existingTest and $test is the same when I dump them. This is cool, and makes me able to get rid of the mentioned $existingTest variable, but makes me wonder if I am understanding PHP’s loop functionality.

Doesn’t the $test variable only exist inside the foreach scope? Does PHP temporarily save the value of the last index the execution has run through?

>Solution :

PHP’s variable scope is explained here: https://www.php.net/manual/en/language.variables.scope.php

Effectively you have 2 scopes:

• The global scope
• The local function scope

So a loop variable will be accessible out of it’s scope and will contain the last value it had. This is why you got this behaviour.

If you have a loop calling a function then you have multiple options:

• Declare the external variable with the global keyword inside the function.
• Access globals with the $GLOBALS variable.
• Pass the globals you need to your anonymous function with the use () syntax.