Parsing a Git Patch with Bash

I probably could have done this in perl and it would have been much faster,but I could say that about a lot of things. My problem is that Perl is not my command-line. Perl can be a REPL, but bash always is a REPL. Ever look at a patch file? If you’re a programmer that deals with patch files, you know there some parts of a patch file that you might not want to keep.