Ternary Comparison Assignment Operators

💡 Ideas
5

You should definitely keep the index instead of a literal for what you called a cycle list:

class CycleList {
	constructor(array) {
		this.array = array;
		this.value = 0;
	}
	get curr() {
		return this.array[this.value %% this.array.length];
	}
	get next() {
		return this.array[++this.value %% this.array.length];
	}
	get prev() {
		return this.array[--this.value %% this.array.length];
	}
	step(offset) {
		return this.array[(this.value += offset) %% this.array.length];
	}
	*[Symbol.iterator]() {
		while (true) {
			yield this.next;
		}
	}
}
const list = new CycleList(["ascending", "descending", "unspecified"]);
list.curr; // "ascending"
list.next; // "descending"
list.step(-2); // "unspecified"

Notice that it uses the proposed Modulo Operator %%.