Re: on the need to duplicate code for procedure signature in both body and interface files

[Shark8 <onewingedshark@gmail.com>]

On Saturday, July 7, 2012 5:08:53 PM UTC-6, Nasser M. Abbasi wrote:
> Basic question from an Ada newbie.
> 
> One thing that always bothered me in Ada is the need
> to physically duplicate the code that represents the API
> of the package procedures and functions in both the interface
> and the body files (.ads and .adb).
> 
> I do not like duplicating code at all. Even if it is only
> for the signature of the API, and even though the Ada
> compiler will catch any difference (assuming one changes
> the .ads and forget to update the .adb for example).
> 
> Was there no other alternatives to avoid this situation
> when Ada was originally designed in order to keep the same
> good concept of separating the interface from the body, but
> somehow at the same time, eliminate the need to duplicate by
> hand the API definition code in 2 separate places?
> 
> I am using GNAT. I Assume this is the same in other Ada
> implementations.
> 
> thanks,
> --Nasser

There is no real way to do clean separate compilation without something like the spec/body separation (though it may be that everything code-wise is the "body" and the "spec" is virtual/internal).

My suggestion here is to let the compiler point out your errors. Unlike C/C++ an Ada compiler is your friend. There might be an adb -> ads generator laying around where you can just feed it an adb file and have it spit out the ads-file, but I've never had reason to look for one.