元组在地图操作中开箱 [英] Tuple Unpacking in Map Operations

问题描述

我经常发现自己与元组的列表，Seqs和迭代器一起工作，并且想做如下的操作：

I frequently find myself working with Lists, Seqs, and Iterators of Tuples and would like to do something like the following,

val arrayOfTuples = List((1, "Two"), (3, "Four"))
arrayOfTuples.map { (e1: Int, e2: String) => e1.toString + e2 }

但是，编译器似乎并不喜欢这种语法。相反，我最终写了，

However, the compiler never seems to agree with this syntax. Instead, I end up writing,

arrayOfTuples.map { 
    t => 
    val e1 = t._1
    val e2 = t._2
    e1.toString + e2 
}

这是愚蠢的。如何解决这个问题？

Which is just silly. How can I get around this?

推荐答案

一个工作是使用 case ：

arrayOfTuples map {case (e1: Int, e2: String) => e1.toString + e2}

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