Good practice related to empty arrays and notices

Question

I started developing something more complex that what I did before and I want to do it "by the book" and I've read that notices should be avoided, even if they don't affect the usability.

So I have a function that checks the URL and splits it into multiple parts. I then use it to generate the pages, but I get a notice on the frontpage as there aren't enough parts.

Here's some code to see what I'm talking about:

$slug = getRightURL();

In getRightURL() I have:

$curURL = $_SERVER['REQUEST_URI'];
$URL = explode('/', $curURL);
return $URL[2];

So when the url is just http://example.com/ the function throws a notice;

I was thinking about adding this:

if(count($URL) > 1) return $URL[1];

But is there a better way to do this?

Answer 1

Just counting doesn't always do the trick as PHP arrays aren't actually arrays (something indexed from 0 to length-1) but maps where you can have all kind of not sequenced strings and numbers as index.

To find out if a particular index exists, use isset().

if(isset($URL[2])) {
    return $URL[2];
}
else {
    return '';
}

You could also shorten this with the ternary operator like so:

return (isset($URL[2]) ? $URL[2] : '');