This is a case where you need to follow up with the programmer.
Ask him why he wrote it this way.
There may be a very good reason.. perhaps this needed to follow the same behavior as existing code and therefore he did a line by line translation on purpose for full compatability. If so, give him points for a decent explaination.
Or perhaps he doesn't know Perl, so he learned it that afternoon to answer the question. If so, give him points for fast and nimble learning skills.
The only disqualifying comment may be "I always program Perl this way. I don't understand that regexp stuff."
