Preg match first word? *Brain Freeze..*

Man… Having a brain freeze… Forgot how to preg match. What I have are user names in multiple formats… “John”, “John Doe”, “James John Doe”. I just want the first name.

So if I use preg_match_all… Would it be something like… /^{abc}/
Then the first index 0 would be the first word.

I have been working too much…