#
# set +o errexit -o noglob is assumed.
#

ex_rtl_lconcat() {
	local _list="${1}" _litem_new="${2}" _sep="${3:- }" IFS="${3:-${IFS}}";
	if [ -n "${_list}" ]; then
		printf "%s%s%s" "${_list}" "${_sep}" "${_litem_new}";
	else
		printf "%s" "${_litem_new}";
	fi;
};

ex_rtl_lfilter() {
	local	_list="${1}" _filter="${2}" _sep="${3:- }" IFS="${3:-${IFS}}"	\
		_filterfl="" _litem="" _litem_filter="" _lnew="";
	if [ -z "${_filter}" ]; then
		echo "${_list}"; return 0;
	else for _litem in ${_list}; do
		_filterfl=0;
		for _litem_filter in ${_filter}; do
			if [ "${_litem_filter}" = "${_litem}" ]; then
				_filterfl=1; break;
			fi;
		done;
		if [ "${_filterfl:-0}" -eq 0 ]; then
			_lnew="${_lnew:+${_lnew}${_sep}}${_litem}";
		fi;
	done; fi;
	echo "${_lnew}";
};

ex_rtl_llength() {
	local _list="${1}" _sep="${2:- }" IFS="${2:-${IFS}}" _litem="" _llength=0;
	for _litem in ${_list}; do
		: $((_llength+=1));
	done;
	echo "${_llength}";
};

ex_rtl_lmatch() {
	local _list="${1}" _item="${2}" _sep="${3}";
	[ -n "$(ex_rtl_lsearch "${_list}" "${_item}" "${_sep}")" ];
};

ex_rtl_lsearch() {
	local	_list="${1}" _filter="${2}" _sep="${3:- }" IFS="${3:-${IFS}}"	\
		_litem="" _litem_filter="" _lnew="";
	if [ -z "${_filter}" ]; then
		echo "${_list}"; return 0;
	else for _litem in ${_list}; do
		for _litem_filter in ${_filter}; do
			if [ "${_litem_filter}" = "${_litem}" ]; then
				_lnew="${_lnew:+${_lnew}${_sep}}${_litem}";
				break;
			fi;
		done;
	done; fi;
	echo "${_lnew}";
};

ex_rtl_lunfold_depends() {
	local _vname_template="${1}" _depends="" _name="" _names=""; shift;
	for _name in "${@}"; do
		if _depends="$(ex_rtl_get_var_unsafe -u "$(eval printf \"%s\" \""${_vname_template}"\")")"\
		&& [ -n "${_depends}" ]; then
			_depends="$(ex_rtl_lunfold_depends "${_vname_template}" ${_depends})";
			_names="$(ex_rtl_lconcat "${_names}" "${_depends}")";
		fi;
		_names="$(ex_rtl_lconcat "${_names}" "${_name}")";
	done;
	echo "${_names}";
};

# vim:filetype=sh