在生产服务器上取消设置错误puma-rails 5

Question

我在rails 5上使用puma + nginx + capistrano部署我的应用程序并使用本教程http://codepany.com/blog/rails-5-puma-capistrano-nginx-jungle-upstart/。我执行了所有步骤。但是当我这样做时：

import UIKit

class Tuner {

        var tuning                  = [String]()
        let tonic: Double           = 261.626   // frequency of middle C
        var index                   = -1
        let centsPerOctave: Double  = 1200.0    // mandated by Scala tuning file format
        let formalOctave: Double    = 2.0       // Double for stretched-octave tunings

init(tuning: [String]) {
        self.tuning                 = tuning

        var notes: (pitchClass: Int, frequency: Double)
        notes = tuning.flatMap(scaleFrequencies)

     // print(frequency)

    }



func pitchClass(pitchClass: Int, _ frequency: Double) -> Int {
    return pitchClass
    }

func frequency(pitchClass: Int, _ frequency: Double) -> Double {
    return frequency
    }



func scaleFrequencies(s: String?) -> (Int, Double) {

    index                  += 1
    var frequency: Double  = 0.0        
    frequency              = processNumerics(numericString: numericString)

    return (index, frequency)
}

我收到以下错误：

start puma-manager

我无法启动我的应用，这里的错误是什么，我无法理解。我怎么能纠正这个？