Permalink
Fetching contributors…
Cannot retrieve contributors at this time
6 lines (3 sloc) 436 Bytes

If the &next argument is provided in the URL then this function will return its value.

If the &next argument is not present then it will return the referrer URL, but only if it's from the same domain. Very useful when you want to return to the same page that you've been before, after completing a certain action, like sign in page or edit of the form.

When nothing is present it will simply return the URL of the welcome page.