an Enum of Arrays would be an enum where each enumerator was a product of each possible enumerator. there would be N^M enumerators where N is the length of the

an Enum of Arrays would be an enum where each enumerator was a product of each possible enumerator. there would be N^M enumerators where N is the length of the array and M is the number of enumerators. for example, if the original type was enum { red, green } then the enum of array[3] would have to be an enum containing the 8 enumerators: { red-red-red, red-red-green, red-green-red, red-green-green ... green-green-green } so that's essentially completely useless. i think the exact same problem would occur with array-of-tagged-union to tagged-union-to-array "transformation". you can't just say "hey: arrays and structs and unions are words and if you can do array of struct and struct of array and enum is also a similar word, then why not enum-of-array?". while tfa talks about "batches" of items with the same tag, and the advantages therein, that isn't something captured by the example given, at least without extending the EoA to a variable sized array of EoA and something else to track the number of items in a "run" (as in RLE). this is better thought of as a data-structure problem than a type theory.