无法将 [-] 应用于 Scala 中的 AnyVal
Cannot apply [-] to AnyVal in scala
我正在编写一些代码来比较两个双精度值并将一个从字符串解析为双精度。如下所示:
val diffFun0 = (dims:Dims) => (dims.score == zippedSubs(dims.dimension_name).trim.toDoubleOption.getOrElse(0))
val diffFun = (dims:Dims) => (dims.score - zippedSubs(dims.dimension_name).trim.toDoubleOption.getOrElse(0)).abs > 0.01
//zippedSubs(dims.dimension_name) is double inside string "0.1" or something else
diffLen0 += ods.dimensions.count(diffFun0) //play.sbt.PlayExceptions$CompilationException: Compilation error[Overloaded method value [-] cannot be applied to (AnyVal)]
diffLen += ods.dimensions.count(diffFun) //works totally fine
IDE 显示 zippedSubs(dims.dimension_name)。trim.toDoubleOption.getOrElse(0) 是双精度类型,当我们使用 == 运算符时一切正常。但在其他情况下则不然。
您将类型 Double
与 Int
混合在一起,结果是 AnyVal
。将 getOrElse(0)
替换为 getOrElse(0.0)
并且一切正常。
"0".toDoubleOption.getOrElse(0)
// val res0: AnyVal = 0.0
"0".toDoubleOption.getOrElse(0.0)
// val res0: Double = 0.0
我正在编写一些代码来比较两个双精度值并将一个从字符串解析为双精度。如下所示:
val diffFun0 = (dims:Dims) => (dims.score == zippedSubs(dims.dimension_name).trim.toDoubleOption.getOrElse(0))
val diffFun = (dims:Dims) => (dims.score - zippedSubs(dims.dimension_name).trim.toDoubleOption.getOrElse(0)).abs > 0.01
//zippedSubs(dims.dimension_name) is double inside string "0.1" or something else
diffLen0 += ods.dimensions.count(diffFun0) //play.sbt.PlayExceptions$CompilationException: Compilation error[Overloaded method value [-] cannot be applied to (AnyVal)]
diffLen += ods.dimensions.count(diffFun) //works totally fine
IDE 显示 zippedSubs(dims.dimension_name)。trim.toDoubleOption.getOrElse(0) 是双精度类型,当我们使用 == 运算符时一切正常。但在其他情况下则不然。
您将类型 Double
与 Int
混合在一起,结果是 AnyVal
。将 getOrElse(0)
替换为 getOrElse(0.0)
并且一切正常。
"0".toDoubleOption.getOrElse(0)
// val res0: AnyVal = 0.0
"0".toDoubleOption.getOrElse(0.0)
// val res0: Double = 0.0