slog: redesign Record

- Return to the implementation consisting of an inline array followed
  by a slice.

- Document the alias problems that can arise.

- Provide Record.Clone to make a deep copy so aliasing bugs can be

- Replace AddAttr with AddAttrs, to permit more efficiently adding
  Attrs, and to provide more implementation flexibility.

- Eliminate random access: support only forward iteration.
  Accomplish it with a method that takes a func(Attr).
  Call this method "Attrs"; the old "Attrs", which returned a []Attr,
  can now be written in terms of the new one.
  We do not provide a way to stop iteration early, because the
  large majority of uses will want to visit all the Attrs.

- Call the constructor NewRecord, not MakeRecord, because Record isn't
  truly a value type.

Change-Id: Iac6843cd8a27e351fc4bde79aa59c6cc2e526e46
Reviewed-by: Alan Donovan <>
Run-TryBot: Jonathan Amsterdam <>
TryBot-Result: Gopher Robot <>
8 files changed
tree: 2e128c0a6436aa7ec93f33b0fc3c44aa7ec4b3da
  1. apidiff/
  2. cmd/
  3. constraints/
  4. devtools/
  5. ebnf/
  6. ebnflint/
  7. errors/
  8. event/
  9. inotify/
  10. io/
  11. jsonrpc2/
  12. maps/
  13. mmap/
  14. rand/
  15. shiny/
  16. shootout/
  17. slices/
  18. slog/
  19. sumdb/
  20. typeparams/
  21. utf8string/
  22. .gitattributes
  23. .gitignore
  24. codereview.cfg
  26. go.mod
  27. go.sum



This subrepository holds experimental and deprecated (in the old directory) packages.

The idea for this subrepository originated as the pkg/exp directory of the main repository, but its presence there made it unavailable to users of the binary downloads of the Go installation. The subrepository has therefore been created to make it possible to go get these packages.

Warning: Packages here are experimental and unreliable. Some may one day be promoted to the main repository or other subrepository, or they may be modified arbitrarily or even disappear altogether.

In short, code in this subrepository is not subject to the Go 1 compatibility promise. (No subrepo is, but the promise is even more likely to be violated by go.exp than the others.)

Caveat emptor.