$bar =~ s/(\d{2})/joo/msg;
$bar =~ s#(\d{2})#jee#msg;
$bar =~ s#(\d{2})#foo($1)#mesg;
$bar =~ s#(\d{2})#<td>ha ha ha</td>#msg;
##</code><code>##

Bareword found where operator expected at a.pl line 18, near "<td>foo"
        (Missing operator before foo?)
syntax error at a.pl line 18, near "<td>foo"
Search pattern not terminated at a.pl line 18.