delete($opts{l}); ## was: delete($opts{L});

##</code><code>##

# was: if (/@(?:([[:word:]:]+)::)?ISA\s*=\s*(.*)\s*/) 
if (/(?<!\\)@(?:([[:word:]:]+)::)?ISA\s*=\s*(.*)/) 

##</code><code>##

while (!/;/)    # accumulate ISA value for multiple lines
{
    $_ = <$f>;
    $tmp .= $_;
}
@isa = eval $tmp;
# was: if ($@) { warn "Unparseable \@ISA line: $_"; next };
       if ($@) { warn "Unparseable \@ISA line: $tmp"; next };