anchor.diff:      /// in the Dictionary, or creates a new entry if one doesn't exist.
       /// If the Dictionary is read-only, an InvalidOperationException is raised.
       [<CompiledName("UpdateOrAdd")>]
  -    let updateOrAdd key value (dict : IDictionary<'Key, 'T>) =
  +    let updateOrAdd key value (dict : dict<'Key, 'T>) =
           // Preconditions
           checkNonNull "dict" dict
               
  
positive.code: /// Applies the given function to sucecssive entries, returning the
  /// first x where the function returns "Some(x)".
  [<CompiledName("Pick")>]
  let pick picker (dictionary : IDictionary<'Key, 'T>) =
      // Preconditions
      checkNonNull "dictionary" dictionary
  
  
negative.code: /// Builds a new Dictionary whose entries are the results of applying
  /// the given function to each element of the Dictionary.
  [<CompiledName("Map")>]
  let map (mapping : 'Key -> 'T -> 'U) (dictionary : dict<'Key, 'T>) =
      // Preconditions
      checkNonNull "dictionary" dictionary
  
  