Method createEffect

tools/common/_hyperscript.iife.js:3338–3354

* Create a reactive effect with automatic dependency tracking. * @param {() => any} expression - The watched expression * @param {(value: any) => void} handler - Called when the value changes * @param {Object} [options] * @param {Element} [options.element] - Auto-stop when elemen

(expression, handler, options)

     * @returns {() => void} Stop function
     */
    createEffect(expression, handler, options) {
      var effect = new Effect(
        expression,
        handler,
        options && options.element || null,
        this
      );
      effect.initialize();
      if (effect.element) {
        var data = effect.element._hyperscript ??= {};
        data.effects ??= /* @__PURE__ */ new Set();
        data.effects.add(effect);
      }
      return function() {
        effect.stop();
      };
    }
    /** Stop all reactive effects owned by an element. */
    stopElementEffects(element) {
      var data = element._hyperscript;