Method Add

cache.go:92–102

Add an item to the cache only if an item doesn't already exist for the given key, or if the existing item has expired. Returns an error otherwise.

(k string, x interface{}, d time.Duration)

// Add an item to the cache only if an item doesn't already exist for the given
// key, or if the existing item has expired. Returns an error otherwise.
func (c *cache) Add(k string, x interface{}, d time.Duration) error {
	c.mu.Lock()
	_, found := c.get(k)
	if found {
		c.mu.Unlock()
		return fmt.Errorf("Item %s already exists", k)
	}
	c.set(k, x, d)
	c.mu.Unlock()
	return nil
}

// Set a new value for the cache key only if it already exists, and the existing
// item hasn't expired. Returns an error otherwise.