Function debounce

packages/markmap-common/src/util.ts:66–93

(
  fn: (...args: T) => U,
  time: number,
)

}

export function debounce<T extends unknown[], U>(
  fn: (...args: T) => U,
  time: number,
) {
  const state: {
    timer: number;
    result?: U;
    args?: T;
  } = {
    timer: 0,
  };
  function reset() {
    if (state.timer) {
      window.clearTimeout(state.timer);
      state.timer = 0;
    }
  }
  function run() {
    reset();
    if (state.args) state.result = fn(...state.args);
  }
  return function debounced(...args: T) {
    reset();
    state.args = args;
    state.timer = window.setTimeout(run, time);
    return state.result;
  };
}