如何重构代码以避免警告:"通过创建2元组来调整参数列表"

Question

以下代码已经过验证,可以正常工作:即将元组添加到现有序列(也是元组)

iter.map { r =>     // Iterator of org.apache.spark.sql.Row
   r.toSeq :+ (outColName,locMap(r.getAs[String](inColName)))
}

但是,我们的构建系统已fail on warning启用并因此错误地输出上述代码:

[info] 'compiler-interface' not yet compiled for Scala 2.10.6. Compiling...
[info]   Compilation completed in 24.504 s
[error] /home/../Sampling.scala:40: Adapting argument list 
         by creating a 2-tuple: this may not be what you want.
[error]         signature: SeqLike.:+[B >: A, That](elem: B)(implicit bf: scala.collection.generic.CanBuildFrom[Repr,B,That]): That
[error]   given arguments: outColName, locMap(r.getAs[String](inColName))
[error]  after adaptation: SeqLike.:+((outColName, locMap(r.getAs[String](inColName))): (String, Int))
[error]           r.toSeq :+ (outColName,locMap(r.getAs[String](inColName)))
[error]                   ^
[error] one error found

现在 - 如上所述 - 这就是我想要的.但Travis需要变得快乐.那么正确的调用是什么来表示相同的 - 这是期望的行为 - 并避免这里的警告？

Answer 1

尝试通过显式添加方法调用和括号来帮助编译器。

iter.map { r: Row => 
   r.toSeq.:+( (outColName,locMap(r.getAs[String](inColName))):Any )
}