[Gnu-arch-users] Adding 'checkouts' to tla (was: file histories)

[Maksim Lin]

> Let's suppose that I have an arch project tree, but that there are
> SCCS directories in this tree, and all of the source files are "doubly
> controlled" -- by both SCCS and arch.


Sorry to be replying to a month old email, but it got me thinking about 
how most of the other scm's also do this sort of thing:

cvs uses rcs
bitkeeper uses sccs
perforce uses rcs

though btw, I think per file history (as touted by bk I believe) doesn't 
seem like a particularly useful thing to me.
but I think adding sccs into tla is probably more of a long term thing...
Back in the present, it got me thinking, what about adding an OPTION to 
have check out semantics to tla?
This would I think bring a number of benefits:
- allow very quick commits, since having to 'checkout' files would 
provide tla with a list of all the files that have been modified, rather 
then scanning the whole project tree.
- allow very quick-what changed commands
- allow what changed command to work without a local prisitine tree or 
looking at the archive!
- allow multiple changesets with new files/dirs and renames
- maybe other stuff I cant think off at the moment... :-)

against this you would lose the ability to use shell commands to add new 
src files just by creating a new file (which you can't do anyways if you 
are using explicit or tagline tagging) or renaming/moving files with 
shell commands.  It is an inconvience to have to check out files before 
editing them, but hey lots of people are used to that anyways. So anyone 
who for instance has a very large tree to deal with could use the option 
to trade-off the inconveince of having to checkout files with the 
benefits of very fast commits. I think this could be added fairly 
easily, just by making all files read-only on a "tla get", then having a 
"tla co" command to checkout a file(s), chmoding them to writable and 
addingthem to a list held in a tla config file. Likewise added new files 
or renaming would need to be done through "tla add" & "tla move".
So Tom does this sound feasible?

Maks.