Function createId

packages/core/src/util/ids.ts:37–58

(proposedId: string)

  iteration <= 1 ? idBase : idBase + iteration.toString();

export const createId = (proposedId: string) => {
  if (proposedId === undefined) {
    // failsafe to avoid endless loops in error cases
    proposedId = 'undefined';
  }
  let state = prefixStates.get(proposedId);
  if (state === undefined) {
    state = { used: new Set<number>(), next: 0 };
    prefixStates.set(proposedId, state);
  }
  // Start from the smallest index that hasn't been allocated for this prefix.
  // Holes left by removeId reset `next`, so released ids are reused.
  let tries = state.next;
  while (state.used.has(tries) || idSlots.has(makeId(proposedId, tries))) {
    tries++;
  }
  const newId = makeId(proposedId, tries);
  state.used.add(tries);
  state.next = tries + 1;
  idSlots.set(newId, { prefix: proposedId, index: tries });
  return newId;
};

export const removeId = (id: string) => {
  const slot = idSlots.get(id);