anchor.diff:              this
   
       //
  -    member __.Iter (action : 'T1 -> 'T2 -> unit) : unit =
  +    member __.Iterate (action : 'T1 -> 'T2 -> unit) : unit =
           Map.iter action left
   
       //
  
positive.code: //
  namespace ExtCore.Collections
  
  open System.Diagnostics
  open LanguagePrimitives
  open OptimizedClosures
  
negative.code: /// A bi-directional map.
  [<Sealed>]
  [<NoEquality; NoComparison>]
  [<DebuggerTypeProxy(typedefof<BimapDebuggerProxy<int,int>>)>]
  [<DebuggerDisplay("Count = {Count}")>]
  type Bimap<'T1, 'T2
      when 'T1 : comparison
  