Get the latest nightly build of Cling (LLVM-based, interactive C++ interpreter) https://root.cern.ch/cling

get-cling.sh

#!/usr/bin/env bash
set -eux

this_dir="$(dirname "$(readlink -f "$0")")"

# TODO replate 'ubuntu.*18' by a regex that matches your distro
#      check https://root.cern.ch/download/cling to see what distros are supported
latest_archive="$(w3m https://root.cern.ch/download/cling | grep -u 'ubuntu.*18' | head -n1 | sed 's/\s\+/ /g' |  awk '{print $3}')"

latest_url="https://root.cern.ch/download/cling/${latest_archive}"

wget -O "${this_dir}/${latest_archive}" "${latest_url}"

install_dir="${this_dir}/cling"
mkdir -p "${install_dir}"
tar xvjf "${this_dir}/${latest_archive}" -C "${install_dir}" --strip-components 1