Re: arch taglines for emacs

[Juri Linkov]

Miles Bader <address@hidden> writes:
> RCS keywords are a form of communication from RCS to the human reader of
> the source code.  Arch taglines, on the other hand, are strictly for the
> use of arch (though I suppose you could choose to use them for similar
> purposes in other tools).  RCS tags change (which can be a huge source
> of problems).  Arch taglines _never_ -- by definition -- change.

You are right: RCS tags have a different purpose.  But what I propose
is only to use the same format, i.e. to enclose arch tags in the $ characters.
This solves many problems: special comment delimiters are not needed anymore,
the $ character delimits the arch tag; whitespace is allowed inside the
arch tag: all whitespace until the $ character is considered as part of tag.
There is no need in special warning (e.g. "Do not change this comment"),
because users already know that everything inside the $ characters
shouldn't be changed manually.

> Because taglines are meant for arch, not for the user, you also probably
> don't want them in a very user-visible location; also arch only searches
> for them in the first and last 1024-byte blocks of the file.

Limiting the search by some constant value is not a good thing.
I have a bad experience with time-stamp Emacs feature.  It limits its
search for a Time-stamp tag by only first 8 lines.  Sometimes, the
line with a Time-stamp tag gets accidentally shifted below 8 lines
(by adding new comment lines above it) and becomes invisible for
time-stamp to update it.  So I would also propose to disable default
limits for time-stamp by setting the default value of the variable
`time-stamp-line-limit' to 0.

> You are right that a less strictly line-oriented syntax would be more
> convenient (in fact such a syntax is being discussed right now on
> gnu-arch-users, in case you're reading this on emacs-devel).

OK, I continued this discussion on gnu-arch-users.

-- 
http://www.jurta.org/emacs/