Swift优雅的处理数组越界问题
2016-07-20 本文已影响85人
南国青天
extension CollectionType {
/// Returns the element at the specified index iff it is within bounds, otherwise nil.
subscript (safe index: Index) -> Generator.Element? {
return indices.contains(index) ? self[index] : nil
}
}
//let label = labels[safe:i]
