second

Originally, rm would merrily nuke your whole filesystem if you told it to. At some point, someone thought that was a pretty stupid default behaviour, so they added that flag to change the default to not nuke your entire filesystem. However, they made the change backwards compatible in case someone still needed the old behaviour. I can imagine in a container or throwaway environment, it might be vaguely reasonable to expect to be able the blat /.

See also:

Unix gives you just enough rope to hang yourself -- and then a couple of more feet, just to be sure.

-- Eric Allman

rm -rf / needs --no-preserve-root on GNU coreutils, I think.

That's a bit of an unfair comparison - that's the GitLab instructions to install from source. Most people use a package (rpm, deb) to install GitLab.

The installation instructions for GitLab from prebuilt binaries is https://about.gitlab.com/install/, and that's significantly shorter.

That said, I think for most home applications, GitLab is hugely overkill.

Are you sure it's not working? Does echo ${arr[@]} return the whole array? Does echo ${arr[1]} return the second value? I think just echoing $arr without specifying an index returns only the first value.