Testing type classes from http://www.nut-cracker.com.ar/index.php/typeclasses-for-fsharp

gistfile1.fs

type Fmap = Fmap with
	static member (?<-) (_, _Functor:Fmap, x:option<_>    ) = fun f -> Option.map f x
	static member (?<-) (_, _Functor:Fmap, g:_->_         ) = (>>) g

let inline fmap f x = (() ? (Fmap) <- x) f

Then in a separate assembly:

type Fmap with
    static member (?<-) (_, _Functor:Fmap, x:list<_>      ) = fun f -> List.map   f x

Yields:
	Warning: Extension members cannot provide operator overloads. Consider defining the operator as part of the type definition instead.
	
If we ignore the warning and still try to do:

let aa = fmap ((*) 3) [1;2;3]

We get:
	Error: No overloads match for method 'op_DynamicAssignment'.
	

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