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DLR interop for F# -- works like dynamic keyword in C#
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FSharp.Interop.Dynamic NuGet Status

The F# Dynamic Operator, powered by the DLR. Compiled for .NET Standard 2.0, .NET Standard 1.6, .NET Framework 4.5

Install from NuGet

PM> Install-Package FSharp.Interop.Dynamic

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Bleeding edge feed on MyGet

MyGet Pre Release


target?Property, target?Property<-value, and target?Method(arg,arg2) allow you to dynamically get/set properties and call methods

Also Dyn.implicitConvert,Dyn.explicitConvert, comparison operators and more.



open FSharp.Interop.Dynamic
let ex1 = ExpandoObject()
ex1?Test<-"Hi"//Set Dynamic Property
ex1?Test //Get Dynamic

MVC ViewBag



open FSharp.Interop.Dynamic
open Dynamitey.DynamicObjects

let ComBinder = LateType("System.Dynamic.ComBinder, System.Dynamic, Version=, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a")

let getPropertyNames (target:obj) =
  seq {
    yield! target.GetType().GetTypeInfo().GetProperties().Select(fun it -> it.Name)
    if (ComBinder.IsAvailable) then
      yield! ComBinder?GetDynamicDataMemberNames(target)

Python Interop

open Python.Runtime
open FSharp.Interop.Dynamic
open FSharp.Interop.Dynamic.Operators
  use __ = Py.GIL()
  let math = Py.Import(“math”)
  math?cos(math?pi ?*? 2) |> printfn “%O”
  let sin = math?sin
  sin 5 |> printfn “%O”
  math?cos(5) ?+? sin(5) |> printfn “%O”

SignalR (.net framework version)

open FSharp.Interop.Dynamic
type MyHub =
    inherit Hub
    member x.Send (name : string) (message : string) =
        base.Clients.All?addMessage(name,message) |> ignore


The DLR is incompatible with interface explicit members, so are these operators, just like C#'s dynamic keyword.

.NET Core 2.0.0 to 2.0.2 had a major bug in the C# dynamic keyword with nested classes inside of generic classes.. You will know it from a substring argument length exception. .NET Framework 4.0+, .NET Core 1.x and .NET Core 2.0.3+ and later are unaffected.


The default maintainer account for projects under "fsprojects" is @fsprojectsgit - F# Community Project Incubation Space (repo management)

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