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Comment by spicypete | Hacker News Reader

Is there any reason you prefer `set -e` over `&&`? I'm curious if this is a readability thing.

I'm firmly in that camp but I also always add `set -eux`, which makes it so much better at debugging as that gives you individual commands it runs before the output of them.

To be clear, the difference is something along this line:

    $ bash -ec 'echo hello && ls -la /tmp/ | grep systemd && false && echo testing'
    hello
    drwx------.   3 root   root      60 Mar 29 18:33 systemd-private-bluetooth.service-yuSMVM
    drwx------.   3 root   root      60 Mar 29 18:33 systemd-private-upower.service-YhHHP2

versus

    $ bash -euxc 'echo hello; ls -la /tmp/ | grep systemd; false; echo testing'
    + echo hello
    hello
    + ls -la /tmp/
    + grep systemd
    drwx------.   3 root   root      60 Mar 29 18:33 systemd-private-bluetooth.service-yuSMVM
    drwx------.   3 root   root      60 Mar 29 18:33 systemd-private-upower.service-YhHHP2
    + false

Docker also supports the `SHELL` syntax now, which is even better, because you can set it once at the top of the Dockerfile without having to do the whole `set -eux` on every line.

Readability is putting it mildly; do you write your shell scripts using that && style? No? Why not, is it for readability?

I also have a hard time reasoning about && with anything other than the most braindead sequence of commands because: $(thing && if other_thing; then inner_thing1 && thing2; fi && ohgawd)

And I just realized while typing that out that if its parser doesn't support ; then I guess one needs to

  RUN if conditional_thing \
      then good_luck && \
      fi && \
      echo "whew"

This is a valid point -- I replied to why this is the way it is here: https://news.ycombinator.com/item?id=43629049. I understand it's not ideal for many, and I am open to PRs!

Reply on news.ycombinator.com