anchor.diff:  
       type LegViewModel(l:Leg) = 
           let mutable leg = l
  -        let mutable strike = 0.0
  +        let mutable strike = "0.0"
           let mutable expiry = "test"
           let mutable kind = "Option"
           let mutable direction = "Buy"       
  
positive.code:         do 
              match l.Definition with
                      | Option opt -> 
                          strike <- opt.Strike
                          expiry <- opt.Expiry |> dateToString
                          direction <- opt.Direction |> getDirection
                          kind <- opt.Kind |> getKind
  
negative.code:                 {
                      Definition = Cash { 
                          Direction = if direction = "Buy" then 1.0 else -1.0
                          Price = float strike
                      }
                      Pricing = None
                  }
  