wishlist: git grep -r

I often use "grep -r $pattern" to recursively grep a source tree. If that takes too long, I hit ^C and tag "git" in front of the command line and re-run it. git then complains "error: unknown switch `r'" because "git grep" is naturally recursive.

Could we have "git grep -r" accept the argument for compatibility? Other important grep switches like "-i" are compatible, adding -r would improve usability.

Thanks, Christoph