这些导入后为什么需要分号？ [英] Why do I need semicolons after these imports?

问题描述

到目前为止，我从未真正在Scala中使用Traits，我想改变它。我有这个代码：

I never really used Traits much in Scala so far, and I want to change this. I have this code:

import tools.nsc.io.Path
import java.io.File

trait ImageFileAcceptor extends FileAcceptor {
    override def accept(f:File) =  {
        super.accept(f) match {
            case true => {
                // additional work to see if it's really an image
            }
            case _ => false
        }
    }
}

问题是，当我用 sbt 编译，我一直收到：

The problem is, when I compile with sbt, I keep receiving:

ImageFileAcceptor.scala：2：' ;'预期但'导入'找到。

如果我在之后添加; 导入，代码编译。这是 FileAcceptor ：

If I add ; after the imports, the code compiles. Here's FileAcceptor:

import java.io.File

trait FileAcceptor extends Acceptable {
    override def accept(f:File):Boolean = f.isFile
}

这里的可接受：

import java.io.File

trait Acceptable {
    def accept(f:File):Boolean
}

我不明白为什么我在进口后需要分号。

I don't understand why I need semicolons after the imports.

编辑：也许输出sbt很有用：

maybe the output of sbt is helpful:

[info] Building project tt 1.0 against Scala 2.8.1
[info]    using sbt.DefaultProject with sbt 0.7.5 and Scala 2.7.7

推荐答案

当scala编译器遇到Macintosh行结尾 - \ r 时 - scala编译器将错误地声明需要分号，因为Moritz如此推断。 Scala参考手册的第1.2节描述了正确的换行符。我在参考文献中找不到哪些字符文字被视为换行符。根据经验，Windows（ \\\\ n ）和Unix（ \ n ）都可以接受。据推测，scala在这方面与Java严格兼容。

When the scala compiler encounters a Macintosh line ending--being \r--the scala compiler will erroneously declare the need for a semi-colon, as Moritz so deduced. Section 1.2 of the Scala Reference Manual describe correct newline characters. I could not find in the Reference which character literals were considered as newlines. From experience, both Windows (\r\n) and Unix (\n) are acceptable. Presumably scala is strictly compatible with Java in this regard.

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