相关疑难解决方法(0)

Swift中是否有flattenScala,Xtend,Groovy,Ruby和co？

var aofa = [[1,2,3],[4],[5,6,7,8,9]]
aofa.flatten() // shall deliver [1,2,3,4,5,6,7,8,9] 

当然我可以使用reduce,但那有点糟透了

var flattened = aofa.reduce(Int[]()){
    a,i in var b : Int[] = a
    b.extend(i)
    return b
}