Function remember

src/expiring-map.ts:23–35

(key: K, factory: () => V)

    },

    remember(key: K, factory: () => V) {
      let result = map.get(key)

      if (result && result.expiration > new Date()) {
        return result.value
      }

      map.delete(key)

      let value = factory()
      this.set(key, value)
      return value
    },

    set(key: K, value: V) {
      let expiration = new Date()