anchor.diff:  open NUnit.Framework
   open System
   open FSharp.Data
  -open FsUnit
   open FsCheck
   
  +[<TestFixtureSetUp>]
  +let fixtureSetup() = 
  +    Runner.init.Force() |> ignore
  +
   #if INTERACTIVE
  -Runner.init.Force()
  +fixtureSetup()
   #endif
   
  -let escaped = Set(['t';'r';'b';'n';'f';'\\';'/';'"'])
  +let escaped = Set(['t';'r';'b';'n';'f';'\\';'"'])
   
   let rec isValidJsonString s = 
       match s with
  
positive.code:     
      let boolGen = Gen.elements ["true"; "false"]
      let nullGen = Gen.constant "null"
  
      let recordGen record =
          record
  
negative.code:     |> Gen.suchThat ((<>) null)
      |> Gen.suchThat (Seq.toList >> isValidJsonString)
  
  let jsonStringGen : Gen<string> =
   
      let validJsonStringGen' = 
  