c:\@Work\Perl>perl -wMstrict -le
"use 5.014;
 ;;
 my %xlate_map = qw/ ( l_paren  ) r_paren  { l_curly  } r_curly /;
 ;;
 sub xlate {
   my ($s, $hr_map) = @_;
   ;;
   my $targets = join '', map quotemeta, keys %$hr_map;
   return $s =~ s{ ([$targets]) }{$hr_map->{$1}}xmsgr;
   }
 ;;
 my $str = 'a { b } c ( d ) e {{F}} ((G))';
 my $xlt = xlate($str, \%xlate_map);
 print qq{'$xlt'};
"
'a l_curly b r_curly c l_paren d r_paren e l_curlyl_curlyFr_curlyr_curly l_parenl_parenGr_parenr_paren'