Scala-4

import scala.io.Source
def widthOfLines(s:String):Int=s.length.toString.length
val f = Source.fromFile("main.scala")
val linesList=f.getLines().toList

val maxLine=linesList.reduceLeft((a:String,b:String)=>
if (a.length>b.length)a
else b)

val padding=widthOfLines(maxLine)  //padding:Int 43 -> 2

for (m<-linesList){
  val lenM=widthOfLines(m)
  println(m.length+" "*(padding-lenM)+"| "+m)

}

import java.io.{PrintWriter, File}
import scala.io.Source
def searchItemFrom(x:Int,c:Char,s:String):AnyVal= //查找字符里的char
  if (x>=s.length)-1
  else if (s(x)!=c) searchItemFrom(x+1,c,s)
  else x

def factoria(x:Int):Int={//求阶乘
  def factoriaInner(a:Int,b:Int):Int={
    if(a<=1&&b<=1)1
    else if(a==1)b
    else factoriaInner(a-1,b*(a-1))
  }
  factoriaInner(x,x)
}

def makeRowSeq(row:Int)={//打印乘法表
    for(col<-1 to 10)yield {
     val prod=(row*col).toString
      val padding=" "*(4-prod.length)
      padding+prod
    }
}
def makeRow(x:Int)=makeRowSeq(x).mkString

def makeTable()={
  val lists=for(row<-1 to 10)yield {
    makeRow(row)
  }
  lists.mkString("\n")
}

def processFile(fileName:String,width:Int)={
  def processLine(line:String)={
    if(line.length>width)println(line)
  }
  val f = new File(fileName)
  val linesList =Source.fromFile(f).getLines().toList
  for(line<-linesList)yield{processLine(line)}

}

object filesFinding{
  val filesHere = (new File(".")).listFiles()
  def filesMatch(query:String,matching:(String,String)=>Boolean)={
    for(f <- filesHere if(matching(f.getName,query)))yield f.getName
  }
}

def containsNeg(l:List[Int]):Boolean=l.exists(_<0)//判断是否有负数
def containsOdd(l:List[Int]):Boolean=l.exists(_%2==1)
val a=List(1,2,3,4)
def withPrintWriter(file:File,op:PrintWriter=>Unit): Unit ={
  val writer = new PrintWriter(file)
   try{
     op(writer)
   } finally {
     writer.close()
   }
}
class A{
  val a=10
}
class B{
  val b=20
}
def process(a:A,op:B=>Unit)={
  val n=new B
  try op(n)
  finally println(a.a)
}

process(new A,b=>println(b.b))