模式匹配中的F#小于算子

由于某些原因，此模式匹配中的小于运算符将不起作用。这是我唯一的错误，让我发疯。 我可能错过了一些非常明显的东西，但非常感谢所有的帮助

let CheckAccount account = 
match account with
| {Balance < 10.00} -> Console.WriteLine("Balance is Low")
| {Balance >= 10.00 and <= 100.00} -> Console.WriteLine("Balance is OK")
| {Balance > 100.00} -> Console.WriteLine("Balance is High")

让支票帐户=
对帐
|{Balance<10.00}->Console.WriteLine（“余额低”）
|{Balance>=10.00和Console.WriteLine（“平衡正常”）
|{Balance>100.00}->Console.WriteLine（“余额高”）

这是一种：

type Account = {AccountNumber:string 
            mutable Balance:float} 
            member this.Withdraw(amnt:float) = 
                if amnt > this.Balance then
                    Console.WriteLine("Unable to withdraw. The Amount you wish to withdraw is greater than your current balance.")
                else
                    this.Balance <- this.Balance - amnt
                    Console.WriteLine("You have withdrawn £" + amnt.ToString() + ". Your balance is now: £" + this.Balance.ToString())
            member this.Deposit(amnt:float) =
                this.Balance <- this.Balance + amnt
                Console.WriteLine("£" + amnt.ToString() + " Deposited. Your new Balance is: £" + this.Balance.ToString())
            member this.Print = 
                Console.WriteLine("Account Number: " + this.AccountNumber)
                Console.WriteLine("Balance: £" + this.Balance.ToString())

type Account={AccountNumber:string
可变平衡：浮动}
此成员。撤消（amnt:float）=
如果amnt>this.Balance，则
Console.WriteLine（“无法提取。您希望提取的金额大于您当前的余额。”）
其他的
this.Balance您可以使用模式匹配提取余额值，将其绑定到新名称，然后使用
when
子句比较值：

let CheckAccount account = 
  match account with
  | {Balance = b} when b < 10.00 -> Console.WriteLine("Balance is Low")
  | {Balance = b} when b >= 10.00 && b <= 100.00 -> Console.WriteLine("Balance is OK")
  | {Balance = b} when b > 100.00 -> Console.WriteLine("Balance is High")

然后您可以使用这些选项：

let CheckAccount account = 
  match account with
  | {Balance = LessThan 10.0} -> Console.WriteLine("Balance is Low")
  | {Balance = LessThan 100.0 & MoreThan 10.0 } -> Console.WriteLine("Balance is OK")

这是相当有趣的，因为你可以使用<代码>和/代码>构造来组合多个活动模式，如<代码> LessThan 100和10以上< /> > 
非常感谢！在写这个答案的过程中我非常分心：-用活动模式添加了更多的东西，而这里提供的答案解决了P问题，我仍然想知道为什么<不起作用。原因是什么？在我看来，任何见解都是对这个答案的一个非常有价值的补充。谢谢！
let CheckAccount account = 
  match account with
  | {Balance = LessThan 10.0} -> Console.WriteLine("Balance is Low")
  | {Balance = LessThan 100.0 & MoreThan 10.0 } -> Console.WriteLine("Balance is OK")