Effect Key

1const objectEffectKeys = new WeakMap<object, string>();
2let nextObjectEffectKey = 1;
3 
4export function effectKey(value: unknown): string {
5  if (value === null) return "null";
6 
7  const valueType = typeof value;
8  if (valueType === "object" || valueType === "function") {
9    return objectEffectKey(value as object);
10  }
11  if (typeof value === "string") return `string:${value.length}:${value}`;
12  if (typeof value === "symbol") {
13    return `symbol:${String((value as symbol).description)}`;
14  }
15  return `${valueType}:${String(value)}`;
16}
17 
18export function joinEffectKey(parts: readonly unknown[]): string {
19  return parts.map(effectKey).join("\u0000");
20}
21 
22function objectEffectKey(value: object): string {
23  const existingKey = objectEffectKeys.get(value);
24  if (existingKey) return existingKey;
25 
26  const key = `object:${nextObjectEffectKey}`;
27  nextObjectEffectKey += 1;
28  objectEffectKeys.set(value, key);
29  return key;
30}