type Group[Kcomparable, Vany] struct {// contains filtered or unexported fields}

func (*Group[K, V])Do¶

func (g *Group[K, V]) Do(key K, fn func() (V,error)) (v V, errerror, sharedbool)

Do executes and returns the results of the given function, makingsure that only one execution is in-flight for a given key at atime. If a duplicate comes in, the duplicate caller waits for theoriginal to complete and receives the same results.The return value shared indicates whether v was given to multiple callers.

func (*Group[K, V])DoChan¶

func (g *Group[K, V]) DoChan(key K, fn func() (V,error)) <-chanResult[V]

DoChan is like Do but returns a channel that will receive theresults when they are ready.

The returned channel will not be closed.

func (*Group[K, V])DoChanContext¶added inv1.68.0

func (g *Group[K, V]) DoChanContext(ctxcontext.Context, key K, fn func(context.Context) (V,error)) <-chanResult[V]

DoChanContext is likeGroup.DoChan, but supports context cancelation. Thecontext passed to the fn function is a context that is canceled only whenthere are no callers waiting on a result (i.e. all callers have canceledtheir contexts).

The context that is passed to the fn function is not derived from any of theinput contexts, so context values will not be propagated. If context valuesare needed, they must be propagated explicitly.

The returned channel will not be closed. The Result.Err field is set to thecontext error if the context is canceled.

func (*Group[K, V])Forget¶

func (g *Group[K, V]) Forget(key K)

Forget tells the singleflight to forget about a key. Future callsto Do for this key will call the function rather than waiting foran earlier call to complete.

type Result[Vany] struct {Val    VErrerrorSharedbool}