Feature to reference a tag

[dakusui]

Following will achieve it.

  function refexists() {
    # shellcheck disable=SC2181
    [[ $? == 0 ]] || abort "${_error_prefix}Failure was detected."
    local _path="${1}"
    has_value_at "${_path}" "$(cat "$(self)")"
  }

  function reftag() {
    # shellcheck disable=SC2181
    [[ $? == 0 ]] || abort "${_error_prefix}Failure was detected."
    local _tagname="${1}"
    local _curpath
    _curpath="$(curn)"
    while [[ "${_curpath}" != "" ]]; do
    _curpath="$(parent "${_curpath}")"
    if refexists "${_curpath}.${_tagname}";  then
      ref "${_curpath}.${_tagname}"
      return 0
    fi
    done
    abort "${_error_prefix}The specified tag:'${_tagname}' was not found from the current path:'$(curn)'"
  }