Howard Abrams has another excellent video up. This one, given to The London Emacs User’s Group, is on eshell. Like me, Abrams has moved as much shell work as possible into
eshell. Unlike me, he’s learned how to take maximum advantage of it. One example of that is learning to make effective use of the Zshell-like glob filters that are built in to
eshell. Every time I see them used, I think to myself that I really need to start using them myself but I never followup. Perhaps this video will provide me with a tipping point.
About half the video is a demonstration of
eshell’s capabilities and some of the ways it differs from a “regular” Unix shell such as Bash or Zshell. One of the major differences is that
eshell effectively has two command parsers. One parses “normal” shell input and the other parses lisp. Interestingly, you can combine the two syntaxes in one input string in useful ways. This part of the video is really interesting and if you’re new to
eshell, it’s probably the most important part. Watching it a couple of times will help jump start your
eshell use and mastery. Abrams has provided a complete transcript of the talk (including the output of the commands he demonstrates) so you don’t have to worry about copying them down from the video.
The second half of the video considers ways of hacking on and extending
eshell. He shows how to do things like writing your own glob filters and leveraging the way pipes are implemented in
eshell. This part is a bit more advanced but necessary if you really want to master
The video is 42 minutes so you’ll have to schedule some time. My only complaint is that the international connection made it difficult to hear to audience’s questions at the end but it’s otherwise a great video and very much worth your time.