地图操作中的元组解包 [英] Tuple Unpacking in Map Operations

问题描述

我经常发现自己在使用元组的列表、序列和迭代器，并且想做类似以下的事情，

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，编译器似乎从不同意这种语法.相反，我最终会写作，

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 
}

这很愚蠢.我该如何解决这个问题?

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

推荐答案

解决方法是使用 case :

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

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