scala中yield使用

定义

一般scala中yield和for循环一起使用，基于原始集合返回一个新可迭代集合，官方文档说明如下

Using yield after for is the “secret sauce” that says, “I want to yield a new collection from the existing collection that I’m iterating over in the for-expression, using the algorithm shown.”

使用

 	val names = List("_adam", "_david", "_frank")
    
    println{ //打印返回的集合
      for(i <- 0 to names.length-1) yield i+names(i)
    }

    println{
        for(name <- names) yield { name.drop(1).capitalize }
    }

打印结果如下

Vector(0_adam, 1_david, 2_frank)
List(Adam, David, Frank)