errata?

[bobate]

A bit confused by what I'm thinking must be typo or update error. Since I'm still in the novice category, I can't figure it out.
On page 142 in the book, it says:
"You’ll have noticed that there are two different variables being set, $jokes and
$error, depending on whether the try block executed successfully."
This is the first time $error appears. I believe it's referring to $e from "(PDOException $e)" but I haven't been able to confirm that despite looking through much of the book, placing errors in the code, searching the pdf version, and searching the website's forums. $e seems to used throughout the book in the try-catch sequences as part of $output. $error seems to be in the template files to be printed out, but I can't find anywhere that it's defined.
What am I missing? Thanks