F＃添加非接口功能到对象表达式

Question

说我有它定义两个函数，Function1和Function2和我使用对象表达式来实现它的接口ICache，但我也希望添加一个辅助函数：

let WebCache = 
    { new ICache with 
     member __.HelperFunction = //this doesn't work! 
     member __.Function1 = foo 
     member __.Function2 = bar 
    } 

F＃似乎不允许你添加任何不属于界面的方法。有没有解决方法？如果我想这样做，我是不是应该首先使用对象表达式？

Answer 1

您可以定义辅助函数作为一个普通的（本地）函数的对象表达之外：

let WebCache = 
    let helper n = 
     printfn "Helping %" n 
    { new ICache with 
     member __.Function1 = helper 1 
     member __.Function2 = helper 2 }