Just a parenthetic note: From Perl version 5.14 on, the  /r modifier for  s/// and  tr/// operators allows them to return the substituted/transformed string for a slightly simpler expression:

c:\@Work\Perl\monks>perl -wMstrict -le
"my $c = qq{foo /* bar \n baz \n boff \n */ fum};
 print qq{<<$c>>};
 ;;
 $c =~ s{ /[*] (.*) [*]/ }{ $1 =~ s{[^\n]}{}xmsrg }xmsge;
 print qq{[[$c]]};
"
<<foo /* bar
 baz
 boff
 */ fum>>
[[foo


 fum]]
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Works with  $1 =~ tr{\n}{}cdr as well. See  s/// in Regexp Quote-Like Operators, and  tr/// in Quote-Like Operators.