withOut<T> function
创建一个剔除所有给定值的新数组
Implementation
List<T> withOut<T>(Iterable<T> list, Iterable<T> values) {
Set<T> tset = Set.from(values);
List<T> rl = [];
for (var e in list) {
if (!tset.contains(e)) {
rl.add(e);
}
}
return rl;
}