#

# 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}";

};

# vim:filetype=sh