Re: resolving ambiguity in action stamps

["Stephen J. Turnbull" <turnbull@sk.tsukuba.ac.jp>]

Eric S. Raymond writes:

 > Both of Harald's objections are, alas, sound.

Only because your requirements are unsound.  It's not possible to
specify a revision compactly, let alone uniquely, in a "preorder of
patches" VCS like Darcs.  (Unlike the example below, it's not always
going to be the case that you can refer to a particular patch as a
summary of the situation.)  So broad portability across VCSes is out.
And it's not really necessary: at any given time there's only going to
be one canonical VCS for a project, so references can (and IMO should)
use that VCS's identifier.

Constructing a reference that is reasonably accurate and meaningful to
humans is also very difficult (at least).  Even restricting yourself
to a single VCS like git, there may be insufficient metadata to remove
ambiguity.  On the other hand, although for academics "Raymond [1997]"
is a form that makes a lot of sense, in referencing commits in a VCS
it's nowhere near as useful.  Human memory for commit content has a
halflife of about 2 weeks -- and that's assuming you were both
following emacs-devel and emacs-commits at the time.  Then you go and
look for it -- guess what, grepping the ChangeLog doesn't work if (as
in many projects, and I understand that many hope Emacs will
eventually be one of them) you don't have ChangeLogs.

I really don't see what's wrong with

2014-09-15  Stefan Monnier  <monnier@iro.umontreal.ca>

* JOKES (dumb_joke_internal):  Revert Eric Raymond's commit of
  2014-04-01 [deadbeefcafefeeddefaceddeafadd0123456789].
  It was a funny-once, Man.

Or whatever formatting you want, as long as the SHA1 ref is easily
parsable out of the text.

Regards,