Re: [PATCH 4/5] branch: restructure -v vs. -vv

Michael J Gruber [off-list ref] writes:

ahead/behind info is expensive, upstream name info cheap. Therefore,
make -v output the upstream branch name and -vv add the ahead/behind
info.

While I do not care too much about the end result, and I even suspect that
swapping the meaning might be better at the semantic level, I do not agree
with the above line of reasoning. It is not based on what the end user
wants at all, but is based on how easily you can produce results.

If a relatively expensive information is what is more often wanted and the
users are willing to pay the price to compute it, it is very reasonable to
use short-and-sweet -v for showing only that information, and have them
type -vv to ask for a less common information.

I also suspect that "ahead/behind" and "who-is-upstream" may be orthogonal
and we may not tie these to degree of verbosity. Jeff's suggestion to
teach these to for-each-ref may be along a similar thought.

You however may be able to argue "When the user wants A/B, s/he always
wants who-is-upstream, and asking for A/B and not wanting who-is-upstream
is insane". If "A/B" does not make sense without seeing "who-is-upstream",
but if seeing "who-is-upstream" alone makes sense without seeing "A/B",
then you can argue that these two are indeed degrees of verbosity, and it
may be justifiable to make -v give "who-is-upstream", and make -vv give
"A/B and who-is-upstream".

But I suspect that much more people have more than one topics cooking on
top of upstream (i.e. need for A/B) than people who work with these topics
based on different upstreams (i.e. need for "who-is-upstream"). People who
base their topics on only one upstream do not need "who-is-upstream" to
understand A/B.

I am wondering if "branch -v=<comma separated tokens>", where currently
available tokens are "sha1", "upstream", "ahead/behind", is the right way
to keep these orthogonal and extensible (of course you would want a
shorter mnemonic). Then existing -v and -vv can be understood as aliases
to:

	-v   ===  -v=sha1,ahead/behind
        -vv  ===  -v=sha1,upstream,ahead/behind

and you can naturally extend the vocabulary with "patchsame" to define
your -vvv introduced in [5/5].