ref: 7d562f0dff4db4ea7f7e91f462c4adf552b1b410 dir: /testdir/t.aeiouy/
/^[^aeiouy]*a[^aeiouy]*e[^aeiouy]*i[^aeiouy]*o[^aeiouy]*u[^aeiouy]*y[^aeiouy]*$/