anchor.diff:      ///
       /// <param name="option">The input option.</param>
       ///
  -    /// <returns>An option of the output type of the binder.</returns>
  +    /// <returns>The input value if the value is Some; otherwise, None.</returns>
       /// <remarks><c>flatten</c> is equivalent to <c>bind id</c>.</remarks>
       ///
       /// <example>
  
positive.code:     ///
      /// <example>
      /// <code>
      ///     (99, None) ||> Option.defaultValue // evaluates to 99
      ///     (99, Some 42) ||> Option.defaultValue // evaluates to 42
      /// </code>
      /// </example>
      ///
  
negative.code:     ///
      /// <param name="voption">The input value option.</param>
      ///
      /// <returns>The input value if the value is Some; otherwise, ValueNone.</returns>
      /// <remarks><c>flatten</c> is equivalent to <c>bind id</c>.</remarks>
      [<CompiledName("Flatten")>]
      val flatten: voption: 'T voption voption -> 'T voption
  