> Introduction of the single pipe operator to represent OR instead of a double pipe operator is baffling in my opinion.

I kind of understand it since it's not a traditional OR operation and intends to keep and associate the matching values, but maybe something like

catch (Exception $e in (Exceptions...))

would make it clearer. Either way, it's so close to feeling like an OR operation that I feel like it will be a lot of debugging when you forget this.