Or you could opt for the old-school approach, and just replace your switch with for, and your whens with if-elsifs: 
for ( $foo ) {
    if    ( tr/I/I/ == 1 ) { $bar = 'low' }
    elsif ( tr/I/I/ == 2 ) { $bar = 'med' }
    elsif ( tr/I/I/ == 3 ) { $bar = 'high' }
    else  { $bar = "drat" }
}

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In reply to Re: switch, transliteration ( tr/// ) of $_ issue by Roy Johnson
in thread switch, transliteration ( tr/// ) of $_ issue by whakka

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