Re: Renames: use of it....

["Grein, Christoph" <christoph.grein@eurocopter.com>]

> Hi all,
> I am doing a code review for a one of the module in flight management
> computer.
> One the procedure is calling an another procedure
> (COMMANDS.EXECUTE_SCROLL) from a package called COMMANDS.
> In package COMMANDS the declaration of the procedure EXECUTE_SCROLL is
> as follows :
> procedure EXECUTE_SCROLL (MCDU_ID   : in
> MMI_APPLICATION_TYPES.T_MCDU_ID;
>                              DIRECTION : in CONTEXT_TYPES.T_DIRECTION)
> renames ACTION_CONTROLER.EXECUTE_SCROLL;
> 
> All the procedures in this package is rename of a procedure in package
> ACTION_CONTROLER or some other package. Why is it so?Why can't use the
> procedure from the package ACTION_CONTROLER itself(i.e instead of
> calling COMMANDS.EXECUTE_SCROLL why can't they use
> ACTION_CONTROLER.EXECUTE_SCROLL)?Is the package COMMANDS really
> required?

This looks very much like a design issue, probably Ada 83. I presume 
ACTION_CONTROLER has more operations than EXECUTE_SCROLL, but only those made 
visible in COMMANDS via renaming statements shall be visible to the outside. So 
there is probably a coding guideline that clients shall use COMMANDS only and 
not ACTION_CONTROLER directly.

This is work-around for the (in Ada 83) missing feature of private children. 
Also in Ada 95, sometimes you cannot make everything private as you would like 
to, so such a rule helps to limit visibility.

In our project, we use a lot of such renaming packages.