If you are interested in more details of the revision walking process,
just have a look at the first implementation of `cmd_log()`; call
~155^2~4` and scroll down to that function (note that you
+`git-show v1.3.04` and scroll down to that function (note that you
no longer need to call `setup_pager()` directly).
Nowadays, `git log` is a builtin, which means that it is _contained_ in the