You say you have problems doing substitutions, but you didn't show us your attempt (despite your claim). You should have no problems using a qr// pattern in a substitution.
I think that misterMatt's problem was that he was trying to stuff a substitution into a qr//, like: 
my $substitution = 's/out/in/';
my $pattern = qr/$substitution/;

[download]
which, naturally, doesn't work (well, doesn't cause a substitution, anyway).

In reply to Re^4: qr// and user provided regex patterns... by JadeNB
in thread qr// and user provided regex patterns... by misterMatt

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