I would write that as: 
my $stars = "*" x 80;
s/^-{40}\cM*$/$stars/;

[download]
Or even 
my $stars = "*" x 80;
my $dashes = "-" x 40;
s/^$dashes\cM*$/$stars/;

[download]

In reply to Re: Is it possible to use repetition within a Regular Expression Substitution? by JavaFan
in thread Is it possible to use repetition within a Regular Expression Substitution? by greatwazzoo

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