“The main problem I had with GNU grep is that I had no way to exclude certain
directories that I knew had nothing of interest for me, like .svn/, CVS/ and
build/. The results from those directories obscured the results I was actually
interested in. There are tools like ack, which skip these directories, but ack
also only grepped files with extensions that it knew about. Furthermore, it had
not implemented the context lines feature, which I had grown accustomed to.
Recent development has added these features, but I had already released grin by
the time I found out.” source...