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Run-time Reflection with Generics - Question
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// Hi, another newbie question about reflection in F#/C#. Let's have:

let f<'t> : string =

    typeof<'t>.Name

// Now these hold:

f<int>     = "Int32"

f<string> = "String"

// But also:

(box f) = (box "Object")

// So by boxing f the type parameter has been coerced to obj with loss of information.

// Can there be an obj that represents f without loss of information?

// Alternatively, can we have:

let g (t : System.Type) =

   // call f with t as the type parameter

// ?

// Thanks, Anton
.
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// Hi, I managed to do this trick with a static method, but still not a module binding.

// It goes like this:

#light

type G = G with

  static member f<'t>() : string = 

    typeof<'t>.Name

      

let g (t : System.Type) =

  typeof<G>.GetMethod("f").GetBaseDefinition().MakeGenericMethod([|t|]).Invoke(null, [||])

    

printfn "%A" (g (typeof<int>)) // "Int32"

printfn "%A" (g (typeof<string>)) // "String"

// So the question transforms into this: 

// How to get at a MethodInfo object corresponding to a method defined in a module?

module M = 

  let f = ()

// how to get at MethodInfo of M.f?

// Thanks, --Anton
By on 11/18/2008 8:36 AM ()

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