cannot be applied to (String) 5.4*"Sally" ^ 也可以直接指定类型如下: val name:type = initialization 例如: val n:Int = 1 例子如下: val whole:Int = 11 val fractional:Double = 1.4 // true or false: val trueOrFalse:Boolean = true val words:String = "A value" val lines:String = ""...
但是,我得到以下错误: [ERROR] [Error] C:\Users\cp740539\IdeaProjects\sparkscala\src\main\scala\au\com\optus\bdp\conversion\PurgingPartitions.scala:213: overloaded method value !! with a lternatives: (log: scala.sys.process.ProcessLogger)String <and> => String cannot be applied to (Int, S...
scala> 1 + oneHalf :10: error: overloaded method value + with alternatives: (x: Double)Double (x: Float)Float (x: Long)Long (x: Int)Int (x: Char)Int (x: Short)Int (x: Byte)Int (x: String)String cannot be applied to (Rational) 1 + oneHalf ^ 整数及其相关类型都没有定义与 R...
<console>:10: error: overloaded method value + with alternatives: (x: Double)Double <and> (x: Float)Float <and> (x: Long)Long <and> (x: Int)Int <and> (x: Char)Int <and> (x: Short)Int <and> (x: Byte)Int <and> (x: String)String cannot be applied to (Rational) 1 + ...
*/object ImplicitClassDemo{implicitclassMyImplicitTypeConversion(val str:String){def strToInt=str.toInt}defmain(args:Array[String]){//compile error!//val max = math.max("1", 2);importcom.github.scala.myimplicit.ImplicitDefDemo.MyImplicitTypeConversion._ ...
scala-maven-plugin不支持完全模式匹配,仅支持/test/scala/和 /main/scala下的模式匹配。故而,在配置文件中需要配置成按包名路径的模式。 Sorry, it was my fault. I didn't realize that /test/ cannot be a part of exclude pattern; patterns only are applied to path inside /test/scala/ or /main/...
(x: String)String cannot be applied to (Rational) 3 + x ^ 可以看到 x+3 没有问题,3 + x 就报错了,这是因为整数类型不支持和Rational相加。我们不可能去修改Int的定义(除非你重写Scala的Int定义)以支持Int和Rational相加。如果你写过.Net代码,这可以通过静态扩展方法来实现,Scala提供了类似的机制来解决这...
<and> (Char)Int <and> (Short)Int <and> (Byte)Int cannot be applied to (Rational) val res2 = 2 * r ˆ 这里的问题是2 * r等同于2.*(r),因此这是在整数2上的方法调用。但Int类没有带Rational参数的乘法——没办法,因为类Rational不是Scala库的标准类。
However, asJavaFunction(rev) will return a java.util.function.Function[String, String] instead.The asJava methods can also be called conveniently from Java. There are additional asScalaFrom methods (e.g. asScalaFromUnaryOperator) that will perform the functional-interface-to-Scala-function ...
println(foo("Some string", "Another string")(3 / 5, 6 / 5), 1) 赋值运算符(Setter 重写) 可以认为重写默认的 setter 是一种使用下划线的转换: class User { private var pass = "" def password = pass def password_=(str: String): Unit = { require(str.nonEmpty, "Password cannot be emp...