As Ordered structs are like rather like arrays, they should have some array like methods for working with keys

• StructPrepend i.e. like javascript unshift

• StructKeyFirst i.e struct.keyArray()[1];

• StructKeyLast i.e struct.keyArray()[struct.len()];

• StructKeyReverse

• StructKeySort

• StructKeyPop

• StructKeyShift

etc

these could simply throw an error if the struct isn't ordered