config/alias.txt: document alias accepting non-command first word

One can see that an alias that begins with a non-command first word,
such as `loud-rebase = -c commit.verbose=true rebase`, is permitted.
However, this isn't immediately obvious to users as alias instances
typically begin with a command.

Document the fact that an alias can begin with a non-command first word
so that users will be able to discover that this is a feature.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Denton Liu 2019-06-05 16:10:13 -04:00 committed by Junio C Hamano
parent 01991cee86
commit 459842e1c2

View file

@ -7,6 +7,16 @@ alias.*::
spaces, the usual shell quoting and escaping is supported.
A quote pair or a backslash can be used to quote them.
+
Note that the first word of an alias does not necessarily have to be a
command. It can be a command-line option that will be passed into the
invocation of `git`. In particular, this is useful when used with `-c`
to pass in one-time configurations or `-p` to force pagination. For example,
`loud-rebase = -c commit.verbose=true rebase` can be defined such that
running `git loud-rebase` would be equivalent to
`git -c commit.verbose=true rebase`. Also, `ps = -p status` would be a
helpful alias since `git ps` would paginate the output of `git status`
where the original command does not.
+
If the alias expansion is prefixed with an exclamation point,
it will be treated as a shell command. For example, defining
`alias.new = !gitk --all --not ORIG_HEAD`, the invocation