问题
Following this question I wonder how (or if) i can extend the generic F# Array Type. I could do this:
type System.Array with
member a.Last = a.GetValue(a.Length - 1)
but as Tomas mentioned it is non generic. Next I tried this but it does not work:
type Microsoft.FSharp.Collections.Array with // Error: Array is not defined
member a.Last = a.[a.Length - 1]
In the F# scource I found this namespace, but it does not work either:
type Microsoft.FSharp.Primitives.Basics.Array with // Error: Array is not defined
member a.Last = a.[a.Length - 1]
回答1:
This is a bit confusing - but I was recently looking for something in the F# specification and came across this:
type 'T ``[]`` with
member a.Last = a.[a.Length - 1]
[| 1 .. 10 |].Last
The double-backtick encoding is normally used to turn reserved keywords into valid F# identifiers (e.g. if you want to have a property that has a space in the name, or is named let). Here, it probably means that the compiler needs to treat [] as an ordinary type "name" rather than as a special syntax for arrays.
来源：https://stackoverflow.com/questions/18359825/f-how-to-extended-the-generic-array-type