package singleflight

import "golang.org/x/build/internal/singleflight"

Package singleflight provides a duplicate function call suppression mechanism.

Index ¶

Package Files ¶

singleflight.go

type Group ¶

type Group struct {
    // contains filtered or unexported fields
}

Group represents a class of work and forms a namespace in which units of work can be executed with duplicate suppression.

func (*Group) Do ¶

func (g *Group) Do(key string, fn func() (interface{}, error)) (v interface{}, err error, shared bool)

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

func (*Group) DoChan ¶

func (g *Group) DoChan(key string, fn func() (interface{}, error)) <-chan Result

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

func (*Group) Forget ¶

func (g *Group) Forget(key string)

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

type Result ¶

type Result struct {
    Val    interface{}
    Err    error
    Shared bool
}

Result holds the results of Do, so they can be passed on a channel.