Simple parentheses balancing method using tailrec

parenthesesBalancing.scala

package week1

import scala.annotation.tailrec

object parenthesesBalancing {

  def balance(chars: List[Char]): Boolean = {

    def analyse(c: Char) =
      if (c == '(') 1
      else if (c == ')') -1
      else 0

    @tailrec
    def loop(cnt: Int, chars: List[Char]): Boolean = {
      if (cnt < 0) false
      else if (chars.isEmpty && cnt == 0) true
      else if (chars.isEmpty && cnt != 0) false
      else loop(cnt + analyse(chars.head), chars.tail)
    }

    loop(0, chars)

  }                                               //> balance: (chars: List[Char])Boolean

  balance("((()()".toList)                        //> res0: Boolean = false

}