5.8.8 is waaaaay old.

That's why

my $CCformatted = $card =~ s/....\K\B/-/gr;

[download]

doesn't work, the /r came along in 5.14. 

my $CCformatted = join '-', $card =~ /..../g;

[download]

should still work.

In reply to Re^4: Formatting with sprintf by Anonymous Monk
in thread Formatting with sprintf by citabriabob

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