anchor.diff:  
   let x: List<int> = []"""
       |> generateDefinitionFromPos (Pos.fromZ 2 7)
  -    |> assertEqual """namespace Microsoft.FSharp.Collections
  +    |> assertSrcAreEqual """namespace Microsoft.FSharp.Collections
   
   /// The type of immutable singly-linked lists.
   [<DefaultAugmentation(false)>]
  
positive.code: let x = Array.map
      """
      |> generateDefinitionFromPos (Pos.fromZ 1 9)
      |> assertEqual """/// Basic operations on arrays.
  [<CompilationRepresentation(enum<CompilationRepresentationFlags> (4))>]
  [<RequireQualifiedAccess>]
  module Microsoft.FSharp.Collections.Array
  
negative.code:         Pos.fromZ 2 17
      ]
      |> List.map (fun pos -> generateDefinitionFromPos pos src)
      |> List.iter (assertSrcAreEqual """/// Basic operations on options.
  [<CompilationRepresentation(enum<CompilationRepresentationFlags> (4))>]
  module Microsoft.FSharp.Core.Option
  
  