“ method_missing”：未定义的局部变量或AppName :: Application：Class的方法“开发”（NameError）

Question

铁路版本-4.2.3 当我尝试在生产环境中启动应用程序

struct ContentView: View {
    @State private var favoriteColor = 0
    var colors = ["Red", "Green", "Blue"]

    var body: some View {
        VStack {
            Picker(selection: $favoriteColor, label: Text("What is your favorite color?")) {
                ForEach(0..<colors.count) { index in
                    Text(self.colors[index]).tag(index)
                }
            }.pickerStyle(SegmentedPickerStyle())
             .cornerRadius(13). ////////////////////////////////--

            Text("Value: \(colors[favoriteColor])")
        }
    }
}

我收到此错误：

/。rvm / gems / ruby​​-2.2.4 / gems / railties-4.2.3 / lib / rails / railtie.rb：196：在rails s RAILS_ENV=production 开发中

Answer 1

尝试：

RAILS_ENV=production rails s

或

rails s -e production

Answer 2

由于在application.rb文件中指定了错误的配置而发生