resolve executable in PATH to nix store

q.sh

# $ q bash
# /nix/store/8wbyyhschvbg0r3p6lh6vpvys6zk4ivc-bash-interactive-4.4-p23/bin/bash
q() {
  readlink -e "$(type -a -p "$@")"
}

# $ qr bash
# /nix/store/8wbyyhschvbg0r3p6lh6vpvys6zk4ivc-bash-interactive-4.4-p23
qr() {
  recurse() {
    local slashes="${1//[^\/]}"
    if [[ "$1" =~ /^\/nix\/store ]] && [ ${#slashes} -gt 3 ]; then
      recurse "$(dirname "$1")"
    else
      printf "%s\n" "$1"
    fi
  }
  recurse "$(readlink -e "$(type -a -p "$1")")"
}