无法实例化包中的scala类

Question

我有三个文件，一个是hi.scala，第二个是hic.scala，第三个是hello.scala。两者的代码如下：

hi.scala

package testpackage.src

package object hi {
    def abs(x: Double) = if (x>=0) x else -x

    def sqrt(x: Double) = {
        def sqrtIter(guess: Double, x: Double): Double =
            if(isGoodGuess(guess,x)) guess
            else sqrtIter(improve(guess,x),x)
        def isGoodGuess(guess: Double, x: Double) =
            abs(guess * guess - x)/x < .0001
        def improve(guess: Double, x: Double) = 
            (guess + x / guess)/2
        sqrtIter(1.0, x)
    }
}

hic.scala

package testpackage.src{

class hic {
    def abs(x: Double) = if (x>=0) x else -x

    def sqrt(x: Double) = {
        def sqrtIter(guess: Double, x: Double): Double =
            if(isGoodGuess(guess,x)) guess
            else sqrtIter(improve(guess,x),x)
        def isGoodGuess(guess: Double, x: Double) =
            abs(guess * guess - x)/x < .0001
        def improve(guess: Double, x: Double) = 
            (guess + x / guess)/2
        sqrtIter(1.0, x)
    }
}

}

hello.scala

import testpackage.src._

object hello {
    def main(args: Array[String]): Unit = {
        println(hi.sqrt(2)) //works fine
        println(hi.abs(-2)) //works fine
        println(new hic) //  error: not found: type hic
        println(new testpackage.src.hic) // error: type hic is not a member of package testpackage.src
    }
}

我可以访问hi.scala文件的hi对象的sqrt和abs方法，但不能实例化hic.scala文件的hic类的对象。我不能理解为什么我不能在包中实例化一个类的对象。

更新:事实证明，代码中没有错误，而是执行方法中有错误。代码给出了以下逗号(@ println(新hic)和println(新testpackage.src.hic))的错误-

scalac *.scala and scala hello.scala

但是，使用以下命令可以很好地运行代码-

scalac *.scala and scala hello

Answer 1

hic.scala中有一对额外的{}。

package testpackage.src{

......

}

我已经测试过在移除它之后一切都很好，除了

println(new platify.src.hic) // error: type hic is not a member of package platify.src

因为platify以前从未发生过。

Answer 2

我认为问题出在包对象hi.scala上。

在您的示例中，如果要将testpackage.src视为包，则包对象应为

package testpackage

package object src {
    def abs(x: Double) = if (x>=0) x else -x

    def sqrt(x: Double) = {
        def sqrtIter(guess: Double, x: Double): Double =
            if(isGoodGuess(guess,x)) guess
            else sqrtIter(improve(guess,x),x)
        def isGoodGuess(guess: Double, x: Double) =
            abs(guess * guess - x)/x < .0001
        def improve(guess: Double, x: Double) = 
            (guess + x / guess)/2
        sqrtIter(1.0, x)
    }
}

Additional Info