php strange behaviour accessing array

Question

I have a function returning an array, called curPageURL. On my local apache, I accessed the return-value of the Page like this: $pageUrl = explode('?',curPageURL())[0]; it worked pretty fine. But on live it didn't work. It took me a lot of time to figure out, that the error was accessing the array.

This solved the issue:

$pageUrl = explode('?',curPageURL());
$pageURL = pageURL[0];


function curPageURL() {
        $pageURL = 'http';
        if (isset($_SERVER["HTTPS"]) && $_SERVER["HTTPS"] == "on") {$pageURL .= "s";}
        $pageURL .= "://";
        if ($_SERVER["SERVER_PORT"] != "80") {
            $pageURL .= $_SERVER["SERVER_NAME"].":".$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"];
        } else {
            $pageURL .= $_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"];
        }
        return $pageURL;
    }

• Can anybody explain why?

• Is it forbidden to access array index directly by function's return value? If so, Why did it worked at my localhost, but not at my live host?

Answer 1

$pageUrl = explode('?',curPageURL())[0]; only available when php version >= 5.4

As of PHP 5.4 it is possible to array dereference the result of a function or method call directly. Before it was only possible using a temporary variable.

Your online host is below that version.

Answer 2

You would need current() until you have PHP 5.4 that supports array dereferencing on function results.

$pageUrl = current(explode('?',curPageURL()));