Re: [PATCH/RFC] Changing submodule foreach --recursive to be depth-first, --parent option to execute command in supermodule as well

Heiko Voigt [off-list ref] writes:

On Mon, Mar 04, 2013 at 03:00:45PM -0800, Junio C Hamano wrote:

quoted

So if you want a single boolean to toggle between the current
behaviour and the other one, it would be --post-order.  But you may
at least want to consider pros and cons of allowing users to give
two separate commands, one for the pre-order visitation (which is
the current "command") and the other for the post-order
visitation. Being able to run both might turn out to be useful.

I second that. Having a --post-order=<command/script> switch will give
us much more flexibility. For ease of use we could allow --post-order
without command to switch the meaning of the main command.

So a final solution would have these switches:

git submodule foreach ... [--pre-order[=<command>]] [--post-order[=<command>]] [<command>]

If only --pre-order without argument is given the command will be
executed pre-order. If only --post-order the command will be executed
post-order. If both are given its an error and so on...

There are some combinations we would need to catch as errors but this
design should allow a step by step implementation:

	1. just the --post-order switch
	2. --post-order with argument switch
	3. --pre-order (including argument) for symmetry of usage

Yeah, I think I can agree with that direction, and Eric's patch
could be that first step of the three-step progression, without
painting us into a corner we cannot get out of when we want to
advance to 2 and 3 later.

I was more interested in the design aspect and I didn't look at the
actual patch text, though.