string.prototype.balanced? = {
  brackets = []
  balanced = true

  my.dice.each_while { c |
    true? c == "["
      { brackets << c }
      { true? c == "]"
        { last = brackets.pop
          false? last == "["
          { balanced = false }
        }
      }

    balanced
  }

  true? brackets.empty?
    { balanced }
    { false }
}

generate_brackets = { n | (n.of("[") + n.of("]")).shuffle.join }

1.to 10 { n |
  test = generate_brackets n

  true? test.balanced?
    { p "#{test} is balanced" }
    { p "#{test} is not balanced" }
}