docs: function(key, oldval, value) {
      if (store._changed_keys.indexOf(key) === -1) {
        store._changed_keys.push(key)
      }
  
      // suppress active timeout (if any)
      if (store._debounce_timeout) {
        store._clearDebounceTimeout()
      }
  
      if (store.options.debounce_ms) {
        // delay event emission and set new timeout id
        store._debounce_timeout = setTimeout(store._publish, store.options.debounce_ms)
      } else {
        // publish immediately
        store._publish()
      }
    }