enum Nucleotide {
    a
    c
    g
    t
}

type Codon = []Nucleotide
type Gene = []Codon

fn test_for_in_alias() {
    mut gene := Gene([
        Codon([Nucleotide.a, Nucleotide.c, Nucleotide.g]),
        Codon([Nucleotide.g, Nucleotide.a, Nucleotide.t]),
    ])

    mut ret := []string{}
    for cdn in gene {
        println(cdn)
        ret << '${cdn}'
    }

    assert ret.len == 2
    assert ret[0] == 'Codon([a, c, g])'
    assert ret[1] == 'Codon([g, a, t])'
}