The first three lines of the example use 3.7.0 as the tarball version. This
is no longer the latest release, which is 3.8.0. (I assume 3.8.0 is "stable".)
Existing example code under Quick Start:
$ wget https://luarocks.org/releases/luarocks-3.7.0.tar.gz
$ tar zxpf luarocks-3.7.0.tar.gz
$ cd luarocks-3.7.0
The front page of https://luarocks.org/ has a "get started" link near the top, leading to: https://luarocks.org/#quick-start , with instructions for a GNU/Linux system.
The first three lines of the example use 3.7.0 as the tarball version. This is no longer the latest release, which is 3.8.0. (I assume 3.8.0 is "stable".)
Existing example code under Quick Start: