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Re: On shipping more of our technical docs as manpages

From
Jeff King <peff@peff.net>
Date
Sep 27, 2018, 06:20 UTC
Message-ID
<20180927062011.GA1318@sigill.intra.peff.net>
In-Reply-To
<878t3oj8em.fsf@evledraar.gmail.com>
On Wed, Sep 26, 2018 at 10:44:33PM +0200, Ævar Arnfjörð Bjarmason wrote:
Show 10 quoted lines
> My bias here is that I've also contributed actively to the perl project
> in the past, and with that project you can get an overview of *all* of
> the docs by typing:
> 
>     man perl
> 
> That includes stuff like perl585delta(1) which we'd stick in
> Documentation/RelNotes, and "Internals and C Language Interface". Most
> of what we'd put in Documentation/technical/api-* & headers is in
> perlapi(1).

I like the perl documentation, too. But I think most of what you're talking about there is the public API, where you have many readers. But here we're talking about internal functions (albeit ones we hope to see reused across the codebase). My concern is mostly: is the work in maintaining this documentation-formatting system worth the number of readers it will get?

There are two numbers there, and I'm guessing at both of them. ;)

If you're interested in pulling documentation out of the header files and generating asciidoc from it, I'm happy to at least try keeping it up to date. When we started putting this information into header files, we used "/**" to start the comment, as a special marker to indicate it was worth pulling out. I don't know how well we've maintained that convention, but it's a starting point.

> I spent an embarrassingly long time submitting patches to git before
> discovering that Documentation/technical/api-*.txt even existed, I think
> something like 1-2 years ago.

That's another thing that I think is improved by keeping the documentation and code together. If you find one, you find the other. You just have to "somehow" find one, which is what you're getting at below.

Show 13 quoted lines
> We have very well documented stuff like strbuf.h (mostly thanks to you),
> but how is such documentation supposed to be discovered? Something like:
> 
>     git grep -A20 '^/\*$' -- *.h
>     <hold in page down>
> 
> ?
> 
> In terms of getting an overview it's indistinguishable from
> comments. I.e. there's nothing like an index of:
> 
>     man git-api-strbuf     ==> working with strings
>     man git-api-sha1-array ==> list, iterate and binary lookup SHA1s

I agree that is a problem, especially for contributors less familiar with the code base. But I think generating an index is a separate (and much easier) problem than formatting all of the documentation.

We already have the /** convention I mentioned above. Could we have another micro-format like:

  /** API:strbuf - working with strings */

in each header file? That would make generating such an index pretty trivial.

> I'm also not in the habit of opening the *.h file for something, I
> usually just start reading the *.c and only later discover there's some
> API docs in the relevant *.h (or not).

Interesting. I'm not totally opposed to putting the documentation alongside the actual code. It does feel a bit cluttered to me, but I think you're right that it keeps everything as close together as possible.

Show 5 quoted lines
> It means you can't avoid seeing it or updating it when source
> spelunking, and it leaves header files short, which is useful when you'd
> like to get a general API overview without all the docs. Our documented
> headers are quite fat, e.g. strbuf.h is 60% of the size of strbuf.c, but
> less than 20% when you strip the docs.

I don't use folds in my editor, and I guess nobody else in this thread does, either. But they may be a reasonable tool for "wow, there are comments, declarations, and definitions all together and I just want to view one of them". In vim, try "set foldmethod=syntax" and then "zc" to close the folds.

I kind of hate it myself, but just another option to explore.
Show 14 quoted lines
> > I'm mildly negative on this, just because it introduces extra work on
> > people writing the documentation. Now it has to follow special
> > formatting rules, and sometimes the source is uglier (e.g., the horrible
> > +-continuation in lists). Are authors now responsible for formatting any
> > changes they make to make sure they look good in asciidoc? Or are people
> > who care about the formatted output going to come along afterwards and
> > submit fixup patches? Either way it seems like make-work.
> 
> This part I'm slightly confused by. If you're just saying "let's
> document stuff in *.h files in free-flowing text", fine. But if we're
> talking about the difference between Documentation/technical/api-*.txt
> and having the same stuff in manpages, then the stuff in api-*.txt *is*
> already asciidoc, and we have a target to format it all up and ship it
> with git, and distros ship that.

Yes, the "free-flowing text" thing is more or less what I'm saying. I suspect what's in technical/* currently probably has formatting problems, and people update it (if we're lucky!) without regard to what the result looks like.

> E.g. on Debian you can "apt install git-doc" and browse stuff like
> file:///usr/share/doc/git-doc/technical/api-argv-array.html which is the
> HTML formatted version, same for all the other api-*.txt docs.

IMHO this is just silly. What am I as an end user going to do with api-argv-array.html?

> This E-mail is much longer than I intended, sorry about that. I didn't
> just mean to bitch about how we ship docs, but I was wondering if there
> was a desire to move to something like what I've outlined above, or
> whether the status quo was mostly by design and intended.

I think we're actually half-way between status quos. The stuff in technical/api-* has existed for a long time. We've been slowly moving stuff over to header files, but there's still a bit of stuff there.

Building those files as asciidoc is one of those things that just cropped up along the way. I have never thought it was useful myself, but somebody bothered to write the patches, so OK. The person who did so is not even somebody who has otherwise worked on the project, AFAICT.

-Peff
Previous: Ævar Arnfjörð BjarmasonNext: Jonathan Nieder
Message 22 of 51 in “[PATCHv3 0/8] fetch: make sure submodule oids are fetched”
  1. Stefan BellerSep 21, 2018
  2. 1/8 sha1-array: provide oid_array_filterStefan Beller, Sep 21, 2018
  3. Ævar Arnfjörð BjarmasonSep 22, 2018
  4. Stefan BellerSep 25, 2018
  5. Jeff KingSep 26, 2018
  6. Junio C HamanoSep 26, 2018
  7. Ævar Arnfjörð BjarmasonSep 26, 2018
  8. Junio C HamanoSep 26, 2018
  9. Jeff KingSep 26, 2018
  10. Ævar Arnfjörð BjarmasonSep 26, 2018
  11. Jeff KingSep 26, 2018
  12. Stefan BellerSep 26, 2018
  13. Junio C HamanoSep 26, 2018
  14. Stefan BellerSep 26, 2018
  15. Junio C HamanoSep 26, 2018
  16. Jeff KingSep 26, 2018
  17. Stefan BellerSep 26, 2018
  18. On shipping more of our technical docs as manpagesÆvar Arnfjörð Bjarmason, Sep 26, 2018
  19. Junio C HamanoSep 26, 2018
  20. Stefan BellerSep 26, 2018
  21. Ævar Arnfjörð BjarmasonSep 27, 2018
  22. Jeff KingSep 27, 2018
  23. Jonathan NiederSep 27, 2018
  24. Jeff KingSep 27, 2018
  25. Junio C HamanoSep 27, 2018
  26. Jeff KingSep 27, 2018
  27. Documentation/CodingGuidelines: How to document new APIsStefan Beller, Sep 27, 2018
  28. Junio C HamanoSep 27, 2018
  29. Ævar Arnfjörð BjarmasonSep 27, 2018
  30. Jonathan NiederSep 27, 2018
  31. Jeff KingSep 28, 2018
  32. Junio C HamanoSep 28, 2018
  33. strbuf.h: format according to coding guidelinesStefan Beller, Sep 28, 2018
  34. Junio C HamanoSep 28, 2018
  35. Junio C HamanoSep 28, 2018
  36. Junio C HamanoSep 28, 2018
  37. Jeff KingSep 29, 2018
  38. Junio C HamanoSep 28, 2018
  39. Stefan BellerSep 28, 2018
  40. Martin ÅgrenSep 28, 2018
  41. Jeff KingSep 29, 2018
  42. Stefan BellerSep 28, 2018
  43. Jeff KingSep 29, 2018
  44. Jeff KingSep 27, 2018
  45. 2/8 submodule.c: fix indentationStefan Beller, Sep 21, 2018
  46. 3/8 submodule.c: sort changed_submodule_names before searching itStefan Beller, Sep 21, 2018
  47. 4/8 submodule: move global changed_submodule_names into fetch submodule structStefan Beller, Sep 21, 2018
  48. 5/8 submodule.c: do not copy around submodule listStefan Beller, Sep 21, 2018
  49. 6/8 submodule: fetch in submodules git directory instead of in worktreeStefan Beller, Sep 21, 2018
  50. 7/8 fetch: retry fetching submodules if needed objects were not fetchedStefan Beller, Sep 21, 2018
  51. 8/8 builtin/fetch: check for submodule updates for non branch fetchesStefan Beller, Sep 21, 2018

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