... # some scope
# pass coderef, returns coderef rebound to this scope
*rebind_here = sub {
   use B::Deparse ();
   ref $_[0] eq "CODE" or die "expected coderef";
   eval("sub ".B::Deparse->new->coderef2text($_[0]));
}
... # some other scope
$new_coderef = &rebind_here($old_coderef);