Re: Report the evolution of Emacs Lisp sources.

[Thien-Thi Nguyen <ttn@gnuvola.org>]

() A Soare <alinsoar@voila.fr>
() Mon, 18 Aug 2008 09:05:01 +0200 (CEST)

   In this moment, the only method to see how the code of emacs
   evaluated is `diff'.

Do you mean to say "evolved" instead of "evaluated"?

   One can show the differences, by comparing the internal
   representation of the lisp code tree of 2 versions. I saw this
   idea for the C code here: [CIL-based AST-diff tool]

   An advantage of this method would be to report only one when
   the name of a variable changes. This method will also ignore to
   report the null-effect characters like blanks or empty new
   lines. diff reports everything.

To its credit, diff can be told to ignore many things, including
certain classes of whitespace.  But your general point stands.

   What do you think, it would be useful such a tool to make
   reports of lisp code changes? Maybe I will try it, but it might
   be _realy_ useful?

Well, there's a lot of noise possible discussing "might be useful"
(see other threads), so i'll just say that personally i would love
to have a tool that could intuit and summarize changes, to help
generate ChangeLog entries.  [dreaming...]  I could hook it up to
a visualization program[0] and make annotated movies, w/ voice
commentary...

     ttn: Ah, now the variable name has changed.  What luck, we
          have the before and after authors here -- WDYT?
 guest-1: Good choice; short, sweet, not too cryptic.
 guest-2: Umm, what does `x' /really/ mean?
 guest-1: You have obviously lost the thread of this patch series.
 guest-2: Not like you have any better idea, you, you... cowboy!
          [clicks ball-point pen furiously]
 guest-1: Well, i guess `long-screen-eating-varname' is better?
          Too much fun with M-/ again, i take it?
          [sneers]
 guest-2: I strive for semantic cohesion, but maybe that's too
          difficult for one-byte GSR-drunk twitchers to grok.
 guest-1: How dare you mock my keyboard-fu!  Cretin!
     ttn: Ah, now the variable name has changed back.  The
          ChangeLog entry mentions "aliasing problems"...
 guest-2: See, see!  It was /you/ who broke the build.
 guest-1: Feh, nobody uses this code anyway.
     ttn: [amidst scuffling sounds] That concludes the audio
          portion of "the underbelly of emacs", please enjoy
          the remaining video portion...

Or maybe not.  :-D

thi

_________________________________________________________________
[0] http://www.gnuvola.org/software/j/buffer-thumbnail/output/