PHP没有在浏览器中显示任何内容[关闭]

I don't know if it's my code or what, but echo is not showing anything.

<?php
function outside() {
    $GLOBALS['variable'] = 'some value';
    inside();
}

function inside() {
        global $variable;
        echo $variable;
}
?>

You're only defining the functions here. You never actually execute either of them. Try adding:

outside();

after the function definitions.

See it in action here: https://eval.in/79203