anchor.diff:    val prepare: Job<#Alt<'x>> -> Alt<'x>
   
     /// Creates an alternative that is computed at instantiation time with the
  -  /// given thunk.
  +  /// given thunk.  See also: `*<-=>`, `prepareJob`.
  +#if DOC
     ///
     /// `prepareFun` is an optimized weaker form of `prepareJob` that can be used
     /// when no concurrent operations beyond the returned alternative are required
     /// by the encapsulated request protocol.
  -#if DOC
     ///
     /// Reference implementation:
     ///
  
positive.code:   ///>   let replyCh = Ch ()
    ///>   counterServer *<+ (n, nack, replyCh) >>-.
    ///>   replyCh
    ///
    /// The client side operation just sends the negative acknowledgment to the
    /// server as a part of the request.  It is essential that a synchronous
  
negative.code: 
    /// Creates an alternative that is computed at instantiation time with the
    /// given job constructed with a negative acknowledgment alternative.  See
    /// also: `*<+->`, `withNackFun`, `prepareJob`.
  #if DOC
    ///
    /// `withNackJob` allows client-server protocols that do require the server to
  