#       argument is non-zero, any existing values will be overwritten and
  #       set back to their default values.
  #
  proc setupRepositoryUriVars { force } {
    #
    # NOTE: The base URI used to build the URIs for the package file server.
    #
    variable baseUri; # DEFAULT: https://urn.to/r

    if {$force || ![info exists baseUri]} then {
      set baseUri https://urn.to/r
    }

    #
    # NOTE: The URI where the package repository server may be contacted to
    #       lookup packages.
    #
    variable lookupUri; # DEFAULT: ${baseUri}/${lookupUrn}