Error on Extension Methods when Inlining

Question

I want to extend some system types and later use them via inlining

type System.String with  
    member this.foo n = this + \"!\" + n 

type System.Boolean w         


        

Answer 1

Statically resolved type constraints do not support extension methods. It's just not a feature of F#.

If you would like F# to gain support for higher-kinded polymorphism, you can vote for it on user voice.