[EUG-LUG:1941] perl: tr/$before/$after/?

[Cory Petkovsek]

How can I use a variable as a search or replace selection using tr//?

$_ = "be!happy";
$before="!;
$after=" ";
tr/$before/$after/;
print $_;


I think it should print this:
be happy

Instead it prints:
af!happy

What can I do?

Thanks,
Cory