Method Set

hashmap.go:164–187

Set sets the value under the specified key to the map. An existing item for this key will be overwritten. If a resizing operation is happening concurrently while calling Set, the item might show up in the map after the resize operation is finished.

(key Key, value Value)

// If a resizing operation is happening concurrently while calling Set, the item might show up in the map
// after the resize operation is finished.
func (m *Map[Key, Value]) Set(key Key, value Value) {
	hash := m.hasher(key)

	for {
		store := m.store.Load()
		searchStart := store.item(hash)

		element, added := m.linkedList.AddOrUpdate(searchStart, hash, key, value)
		if !added {
			continue // a concurrent add did interfere, try again
		}

		count := store.addItem(element)
		currentStore := m.store.Load()
		if store != currentStore { // retry insert in case of insert during grow
			continue
		}

		if m.isResizeNeeded(store, count) && m.resizing.CompareAndSwap(0, 1) {
			go m.grow(0, true)
		}
		return
	}
}

// Grow resizes the map to a new size, the size gets rounded up to next power of 2.
// To double the size of the map use newSize 0.