CSV parser in Scala

CSV.scala

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 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
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 * See the License for the specific language governing permissions and
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import scala.language.postfixOps
import scala.util.parsing.combinator.RegexParsers

// A CSV parser based on RFC4180
// http://tools.ietf.org/html/rfc4180

object CSV extends RegexParsers {
  override val skipWhitespace = false   // meaningful spaces in CSV

  def COMMA   = ","
  def DQUOTE  = "\""
  def DQUOTE2 = "\"\"" ^^ { case _ => "\"" }  // combine 2 dquotes into 1
  def CRLF    = "\r\n" | "\n"
  def TXT     = "[^\",\r\n]".r
  def SPACES  = "[ \t]+".r

  def file: Parser[List[List[String]]] = repsep(record, CRLF) <~ (CRLF?)

  def record: Parser[List[String]] = repsep(field, COMMA)

  def field: Parser[String] = escaped|nonescaped

  def escaped: Parser[String] = {
    ((SPACES?)~>DQUOTE~>((TXT|COMMA|CRLF|DQUOTE2)*)<~DQUOTE<~(SPACES?)) ^^ {
      case ls => ls.mkString("")
    }
  }

  def nonescaped: Parser[String] = (TXT*) ^^ { case ls => ls.mkString("") }

  def parse(s: String): List[List[String]] = parseAll(file, s) match {
    case Success(res, _) => res
    case e => throw new Exception(e.toString)
  }

  def parseLine(s: String): List[String] = parse(s).head

  def main(args: Array[String]) {
    assert(CSV.parseLine( """"a",2,"b","c's'",5""") == List("a", "2", "b", "c's'", "5"))
    assert(CSV.parseLine( """1997,Ford,E350,"Super, ""luxurious"" truck"""") ==
      List("1997", "Ford", "E350", """Super, "luxurious" truck"""))
    assert(CSV.parseLine("") == List(""))
  }
}