Ada aspects which are private to a package -

Assume that I have the most stupid ring buffer in the world.

  Size: Stable: = 16; Subtype T is integer; Package RingBuffer Push Process (value: T); Function Returns Pop; End; Package Body RingBuffer buffer: array of t (0 ... size); Readptr: Integer: = 0; Writeptr: integer: = 1; Process Push (value: T) buffer start (writeptr): = value; Writeptr: = (writeptr + 1) modern shape; End; Function Pop Returns Start T REPTR: = (PHTPTR + 1) Mod Sizes; Return buffer (PETPTR); End; End;   
 Because my code is useless, I want to add pre-condition and postcinding so that I do not abuse it. Therefore, I change the implementation of Push as follows:  
  Process Push (value: T) with pre = & gt; Readptr / = writeptr is the starting buffer (writeptr): = value; Writeptr: = (writeptr + 1) modern shape; End;   
 However, I get a compilation error because I have to introduce the introduction definitions in the process announcement, not in the implementation.  
 The thing is a package is that my announcement is public, the predefined values ​​are related to the package body, which is not visible for the announcement. In order to keep the definition of aspect in the announcement, I want to refactor my code to expose the details of implementation in the public part of the package (in this case,  readptr  and  writeptr < / code>). And I do not want to do this.  
 I can think of some ways around it, like my  push ()  a private  PushImpl ()  process only in that body Is defined which is the pre-condition ... but it is terrible what is the right way to do it?   
 
 
 I think this will always be a problem when verification checks are private, and to check it To declare a function for:  
  The package RingBuffer function is Is_Full return Boolean; Process Push (value: T) with pre = & gt; Not Is_Full; Function Returns Pop;   
 ( Is_Full  is probably useful anyway; in other cases this can not happen).  
 If you leave the implementation in the package body, youâ € ™ ll also have to enter  Is_Full , but you can take them into the spec and using the expression function Can:  
  Package RingBuffer function is_Full return boolean; Process Push (value: T) with pre = & gt; Not Is_Full; Function Returns Pop; Private buffer: array of T (0..size); Readptr: Integer: = 0; Writeptr: integer: = 1; The function is_Full return boolean (readptr = writewriter); Ending buffer;