Actually#2 now that I think about it, one could define a function that
preprocesses the tuple into something that has the type:
const SExpr : type = struct {
symbol : Symbol,
pair : struct {
left : *SExpr,
right : *SExpr,
},
nil : void,
// etc etc
};(Where symbol could be an integer hash of the tag names)
Once you have this, It should not be hard to make an interperter
Additionally, if we really wanted a the previous representation,
we could make a function that converts a comptime known SExpr back
into nested tuples like before