ref: 10e72d182aad860492f6ec2e80b0c05a4dc20b7a dir: /test/t.aeiouy/
/^[^aeiouy]*a[^aeiouy]*e[^aeiouy]*i[^aeiouy]*o[^aeiouy]*u[^aeiouy]*y[^aeiouy]*$/