Well yes but I've always seen immutable DS as synonymous for persistent DS. What OP refers to I've found to be referred to as fixed, const, const static, or com

Well yes but I've always seen immutable DS as synonymous for persistent DS. What OP refers to I've found to be referred to as fixed, const, const static, or compile-time static data structures. Of course naming in CS and Math is terrible and we love reusing terminology so that everything is confusing but that's just where we are. I wasn't trying to be negative towards OP or anything. I just saw that since their comment was downvoted so heavily (which it really shouldn't have been), it might be beneficial to reply with an explanation to clear up any misconceptions and smooth out the conversation.