flatMap.bat

::#! 2>/dev/null || echo "
@echo off
call scala -savecompiled %~f0 %*
goto :eof
" >//null 
#!/bin/sh
exec scala -savecompiled "$0" "$@"
::!#

args match {
	case Array(regex) => // OK
	case _ => {
		println("""
			| Transform lines to more lines based on groups of a regex.
			| Each group in each match becomes a new line.

			| Usage:
			|   map "<regex>"

			| Examples:
			|   (echo a1a2 && echo b3b4) | map "[a-z]([^3])"
			|     1
			|     2
			|     4
		""".stripMargin)
		exit
	}
}

import scala.io._

val lines = Source.stdin.getLines

val MapPattern = args(0).r

lines flatMap { x => for (m <- MapPattern.findAllIn(x).matchData) yield m.subgroups.filter(_ != null).mkString } filter {!_.isEmpty} foreach println