Re: [PATCH] fmt-merge-msg: avoid open "-|" list form for Perl 5.6

Linus Torvalds [off-list ref] writes:

There are many portable interpreters out there, and I don't mean perl. And 
writing a small "specialized for git" one isn't even that hard. In fact, 
most of the shell (and bash) hackery we do now would be unnecessary if we 
just made a small "git interpreter" that ran "git scripts".

Before anybody mentions tcl ;-).

I agree with the above in principle, but I am afraid that is
only half of the solution to the problem Alex is having.

In the longer term, libified git with script language bindings
would make the way git things work together a lot better.  I've
always wanted to make merge-base a subroutine callable from
other things, so that I can say "git diff A...B" to mean "diff
up to B since B forked from A" ;-).

That way, we would eliminate the current common pattern of
piping rev-list output to diff-tree, or ls-files/diff-files
output to update-index --stdin.  These components live in the
single process, a calling "git script", and will talk with each
other internally.

But we do need to talk to non-git things.  git-grep needs a way
for ls-files to drive xargs/grep, for example.  diff --cc reads
from GNU diff output.  And for these external tools, the way
they expect the input to be fed to them or their output is taken
out is via UNIXy pipe.

And the breakage Alex wants to work around is that the platform
is not friendly to pipes, if you deny Cygwin.  So I suspect
avoiding shell would not help much.