Concatenates all files in current directory and subdirectories, inserting filename before each new file. Set to process only .scala files by default.

concatenate

import java.io.File
import scala.io._
import scala.util.matching.Regex
 
def recursiveListFiles(f: File, r: Regex): Array[File] = {
val these = f.listFiles
val good = these.filter(f => r.findFirstIn(f.getName).isDefined)
	good ++ these.filter(_.isDirectory).flatMap(recursiveListFiles(_,r))
}
 
val f = new File(".")
 
val files = recursiveListFiles(f,""".*\.scala$""".r)
 
val result = files.flatMap(f => List(
	"", "",
	"/**",
	" * file " + f.getPath,
	" */", "",
	Source.fromFile(f, "utf-8").mkString
)) mkString "\n"
 
val printer = new java.io.PrintWriter("out1.scala","utf-8")
printer println result
printer.close