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scope - Is it possible to access outer local variable in PHP?

Is it possible to access outer local varialbe in a PHP sub-function?

In below code, I want to access variable $l in inner function bar. Declaring $l as global $l in bar doesn't work.

function foo()
{
    $l = "xyz";

    function bar()
    {
        echo $l;
    }
    bar();
}
foo();
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You could probably use a Closure, to do just that...


Edit : took some time to remember the syntax, but here's what it would look like :

function foo()
{
    $l = "xyz";
    $bar = function () use ($l)
    {
        var_dump($l);
    };
    $bar();
}
foo();

And, running the script, you'd get :

$ php temp.php
string(3) "xyz"


A couple of note :

  • You must put a ; after the function's declaration !
  • You could use the variable by reference, with a & before it's name : use (& $l)

For more informations, as a reference, you can take a look at this page in the manual : Anonymous functions


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