Question

I want my function to access an outside variable—from its parent function specifically. However, using the global keyword sets too broad a scope; I need to limit it. How do I get this code to spit out ‘Level 2’ instead of ‘Level 1’? Do I have to make a class?

<?php
$a = "Level 1";

function first() {
    $a = "Level 2";

    function second() {
        global $a;
        echo $a.'<br />';
    }

    second();
}

first();
//outputs 'Level 1'
?>

Answer 1

PHP has no concept of nested functions or scopes and it’s terrible practice to nest functions. What happens is that PHP simply encounters a function declaration and creates a normal function second. If you try to call first again, PHP will again encounter a function declaration for second and crash, since the function second is already declared. Therefore, don’t declare functions within functions.

As for passing values, either explicitly pass them as function parameters or, as you say, make a class if that makes sense.