/src/golang.org/x/sync - ActiveState ActiveGo 1.8
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Directory /src/golang.org/x/sync

Name Synopsis
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errgroup Package errgroup provides synchronization, error propagation, and Context cancelation for groups of goroutines working on subtasks of a common task.
semaphore Package semaphore provides a weighted semaphore implementation.
singleflight Package singleflight provides a duplicate function call suppression mechanism.
syncmap Package syncmap provides a concurrent map implementation.