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:                     Definition = Option { 
                          Direction = if direction = "Buy" then 1.0 else -1.0
                          Expiry = DateTime.Now
                          Strike = strike
                          PurchaseDate = DateTime.Now
                          Kind = if kind = "Put" then Put else Call
                          Style = European
  
negative.code:                 {
                      Definition = Cash { 
                          Direction = if direction = "Buy" then 1.0 else -1.0
                          Price = float strike
                      }
                      Pricing = None
                  }
  