Translate English to Pig Latin with ease!

platin.p6

multi MAIN($arg where *.IO.f) {
    say translate($arg.IO.slurp).Str
}

multi MAIN($arg) {
    say translate($arg).Str
}

sub translate(Str:D $english) { $english.words.map: &translate-word }

sub translate-word($word) {
    # 'y' is left in the consonants because
    # in English it is always a consonant when
    # at the beginning of a word.
    my @vowels =  <a e i o u A E I O U>;
    my @consonants = (("a".."z", "A".."Z") (-) @vowels).keys.cache;
    given $word {
        when $word.starts-with(any(@vowels)) {
            $word ~ 'yay';
        }
        when $word.starts-with(any(@consonants)) {
            samecase(
                ([~] $word.comb(/./).cache.rotate(1)) ~ 'ay',
                $word ~ 'ay'
            );
        }
        default { $word }
    }
}