///
/// Get single value from key in instance map based on $selector::$key
///
/// @access private
///
/// @param {String}  $key    - breakpoint key to pass to instance method
/// @param {ArgList} $values - list of keys to fetch value from
///
/// @return {*}
///
/// @group Internal Functions
///
@function flint-get-instance-value($key, $values...) {
	@return flint-map-fetch($flint__instances, flint-has-family-instance($key), $values...);
}