#
# set +o errexit -o noglob -o nounset is assumed.
# N.B.	Lists separated by SP, when passed to rtl_l*() w/ explicit IFS,
#	must specify "<SP><VT>" as IFS.
#

rtl_lassign() {
	local	_vnames="${1}" _sep="${2}" _vname="" _vval=""\
		IFS RTL_LFIRST_HEAD="" RTL_LFIRST_TAIL="";
	IFS="${_sep}"; shift 2;
	for _vval in ${@}; do
		if ! rtl_lfirst "${_vnames}" " "; then
			return 1;
		else
			_vname="${RTL_LFIRST_HEAD}"; _vnames="${RTL_LFIRST_TAIL}";
			rtl_set_var_unsafe "${_vname}" "${_vval}";
		fi;
	done;
};

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;
};

rtl_lfilter() {
	local	_list="${1}" _filter="${2}" _sep="${3:- }" IFS="${3:-${IFS:- }}"\
		_filterfl="" _litem="" _litem_filter="" _lnew="";
	if [ -z "${_filter}" ]; then
		printf "%s" "${_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;
	printf "%s" "${_lnew}";
};

rtl_lfilter2() {
	local	_rlist="${1#\$}" _rlist_new="${2#\$}" _filter="${3}" _sep="${4:- }" IFS="${4:-${IFS:- }}"\
		_filterfl="" _litem="" _litem_filter="" _lnew="";

	if [ "${_filter:+1}" != 1 ]; then
		eval ${_rlist_new}=; return 0;
	else	eval set -- '${'"${_rlist}"'}'\; ${_rlist_new}=;
		while [ "${#}" -gt 0 ]; do
			_litem="${1}"; shift; _filterfl=0;
			for _litem_filter in ${_filter}; do
				if [ "${_litem_filter}" = "${_litem}" ]; then
					_filterfl=1; break;
				fi;
			done;
			if [ "${_filterfl:-0}" -eq 0 ]; then
				eval ${_rlist_new}='${'"${_rlist_new}"':+${'"${_rlist_new}"'}${_sep}}${_litem}';
			fi;
		done;
	fi;
};

rtl_lfilter3() {
	rtl_lfilter2 "${1}" "${1}" "${2}" "${3:-}";
};

rtl_lfirst() {
	local _list="${1}" _sep="${2}" IFS; IFS="${_sep}";
	set -- ${_list}; RTL_LFIRST_HEAD="${1}";
	if [ "${#}" -ge 0 ]; then
		shift; RTL_LFIRST_TAIL="${*}";
	else
		RTL_LFIRST_TAIL="";
	fi;
};

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

rtl_llength2() {
	local _rlist="${1#\$}" _rlen="${2#\$}" _sep="${3:- }" IFS="${3:-${IFS:- }}";
	eval set -- '${'"${_rlist}"'}'\; ${_rlen}='${#}';
};

rtl_llift() {
	local _list="${1}" _sep="${2}" _sep_new="${3}" IFS; IFS="${_sep}";
	set -- ${_list}; IFS="${_sep_new}";
	printf "%s" "${*}";
};

rtl_llift2() {
	local	_rlist="${1#\$}" _rlist_new="${2#\$}" _sep="${3}"	\
		_sep_new="${4}" IFS; IFS="${_sep}";

	eval set -- '${'"${_rlist}"'}'; IFS="${_sep_new}";
	eval ${_rlist_new}='"${*}"';
};

rtl_llift3() {
	rtl_llift2 "${1}" "${1}" "${2}" "${3}";
};

rtl_lmatch() {
	local _list="${1}" _item="${2}" _sep="${3:- }";
	[ -n "$(rtl_lsearch "${_list}" "${_item}" "${_sep}")" ];
};

rtl_lmax() {
	local _len=0 _len_max=0;
	while [ "${#}" -gt 0 ]; do
		_len="${#1}";
		if [ "${_len}" -gt "${_len_max}" ]; then
			_len_max="${_len}";
		fi; shift;
	done; printf "%s" "${_len_max}";
};

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

rtl_lsearch_patternl() {
	local	_list="${1}" _pattern="${2}" _sep="${3:- }" IFS="${3:-${IFS:- }}"\
		_litem="" _lnew="";
	if [ -n "${_pattern}" ]; then
		for _litem in ${_list}; do
			if [ "${_litem#${_pattern}}" != "${_litem}" ]; then
				_lnew="${_lnew:+${_lnew}${_sep}}${_litem}";
			fi;
		done;
	fi;
	printf "%s" "${_lnew}";
};

rtl_lsort() {
	local _list="${1}" _sep="${2:- }";
	printf "%s" "${_list}" | tr "${_sep}" "\n" | sort | paste -s -d "${_sep}";
};

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

# vim:filetype=sh