package main
import java.io.File

/**
  * Created by claudio on 06/10/16.
  */
object main extends App{
  println("Chapter 6: Built-in command structures")
  println("\nGrepping '.*' from files in 'prova' directory")
  val files = new File("prova").listFiles

  def grep(pattern: String) {
    def fileLines(file: File) = scala.io.Source.fromFile(file).getLines().toList
    for {
      file <- files
      if file.isFile
      line <- fileLines(file)
      trimmed = line.trim
      if trimmed.matches(pattern)
    } println(file+": "+trimmed)
  }
  grep(".*")

  println("\nListing all .scala files in 'prova' directory")
  def scalaFiles =
    for{
      file <- files
      if file.getName.endsWith(".scala")
    } yield file
  val stairwayFiles = scalaFiles
  stairwayFiles.foreach(f => println(f))
}