for 循环中的 Scala println
下面的 Scala 代码正如我所期望的那样 - 它打印 some_file.txt 的每一行。
import scala.io.Source
val lines = Source.fromPath("some_file.txt").mkString
for (line <- lines) print(line)
如果我使用 println 而不是 print，我希望看到 some_file.txt 以双倍行距打印出来。相反，程序会在 some_file.txt 的每个字符后打印一个换行符。有人可以向我解释一下吗？我正在使用 Scala 2.8.0 Beta 1。
The following Scala code does just what I expect it to - it prints each line of some_file.txt.
import scala.io.Source
val lines = Source.fromPath("some_file.txt").mkString
for (line <- lines) print(line)
If I use println instead of print, I expect to see some_file.txt printed out with double-spacing. Instead, the program prints a newline after every character of some_file.txt. Could someone explain this to me? I'm using Scala 2.8.0 Beta 1.
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lines是单个字符串，而不是某个可迭代的字符串容器。这是因为您调用了.mkString方法。当您迭代一个字符串时，您一次会迭代一个字符。因此，
for中的line实际上并不是一行，而是单个字符。您可能想要做的是调用
.getLines而不是.mkStringlinesis a single string, not some iterable container of strings. This is because you called the.mkStringmethod on it.When you iterate over a string, you do so one character at a time. So the
linein yourforis not actually a line, it's a single character.What you probably intended to do was call
.getLinesinstead of.mkString我怀疑
for (line <-lines) print(line)不会在line中放置一行，而是放置一个字符。由于\n也在那里，所以输出符合预期。当您将print替换为println时，每个字符都会获得自己的行。I suspect that
for (line <- lines) print(line)doesn't put a line inlinebut instead a character. Making the output as expected since the\nis there too. When you the replace theprintwithprintlnevery character gets its own line.