I started doing something like this after I came across a node a while back. I cannot find the link to the node now.

My test code was

use B::Deparse;

my $sr = sub { print "Hello\n" };

$sr->();

my $code = B::Deparse->new->coderef2text($sr);

$code =~ s/print \s\S+/die "Bye";/;

$sr = eval "sub $code";

$sr->();
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