Error: This expression was expected to have type byte [] but here has type 'a * 'b * 'c" in F#

Question

   let IndexOf (searchWithin:byte[])(searchFor:byte[])(startIndex:int):(int) =
      //Function defination
   0

   //calling thisfunction using below
   let endIndex = IndexOf(data, delimiterBytes, startIndex)

   //data is type of byte[], delimiterBytes is also type of byte[] and 
   //startIndex is type of interger.

我收到类似 "This expression was expected to have type byte [] but here has type 'a * 'b * 'c" 的错误。我不明白 'a * 'b * 'c 是什么意思以及为什么它显示错误。谢谢

Answer 1

问题是您的函数定义采用所谓的柯里化形式，例如

let t a b c = ...

需要这样使用：

t 1 2 3

您可以将声明更改为元组形式

let t (a,b,c) = ...

或将用法更改为

t 1 2 3

这是咖喱形式。

有关差异的更多信息，请参见此处的示例：F# parameter passing

Error: This expression was expected to have type byte [] but here has type 'a * 'b * 'c" in F#

Error: This expression was expected to have type byte [] but here has type 'a * 'b * 'c" in F#

f#

function

f#-3.0