cmd/go/internal/par: add Queue as a simpler alternative to Work

par.Work performs two different tasks: deduplicating work (a task
which overlaps with par.Cache), and executing limited active work in
parallel. It also requires the caller to re-invoke Do whenever the
workqueue transititions from empty to non-empty.

The new par.Queue only performs the second of those two tasks, and
presents a simpler API: it starts and stops its own goroutines as
needed (indicating its idle state via a channel), rather than
expecting the caller to drive the transitions explicitly.

For #36460

Change-Id: I5c38657dda63ab55718497467d05d41744ff59f2
Run-TryBot: Bryan C. Mills <>
TryBot-Result: Gobot Gobot <>
Reviewed-by: Jay Conrod <>
2 files changed
tree: abb169b4571b6720b512dfb68ffc5bb5b3057895
  1. .gitattributes
  2. .github/
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  11. api/
  12. doc/
  13. favicon.ico
  14. lib/
  15. misc/
  16. robots.txt
  17. src/
  18. test/

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