I defined for our current project that exception handlers must be written as:

eval {
    # Do stuff
}; if (my $e = $@) {
    # Handle any errors
}
[download]

This brings the commonly used "e" into the game. I think this makes it more obvious what's happening here.

Ok, in this project it gets even easier:

eval {
    # Do stuff
}; if (my $e = $@) {
    unless (UNIVERSAL::isa($e, 'Our::Project::Exception')) {
        $e = Our::Project::Exception::ThirdPartyError->new($e);
    }
    # Handle any errors
}
[download]