Since I often use "TMP" as a name both for files and branches, I wasn't that suprised recently when
gitk TMP
complained that "TMP" was ambiguous and asked me to use -- to separate filenames from revisions. I was a bit more surprised when it still did that after I gave it
gitk TMP --
I looked through the source code very quickly but it wasn't obvious to me why this was happening. The reverse,
gitk -- TMP
interestingly doesn't seem to have the same problem.
--b.