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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Can .ads be compiled alone?
Date: Mon, 17 Nov 2014 06:50:24 +0000
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Date: 2014-11-17T06:50:24+00:00
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rriehle@itu.edu writes:

> The code, in the example, which I originally published in my book, Ada
> Distilled, was compiled with GNAT.  I first compiled the
> specification, and then the body.

The trouble is that if you use GNAT to compile a spec that needs a body
you get

   $ gnatmake -c -u -f driver.ads
   gcc -c driver.ads
   cannot generate code for file driver.ads (package spec)
   gnatmake: "driver.ads" compilation error

and this confuses a *lot* of new users.

The latest Emacs ada-mode doesn't offer a 'compile current file'
option. Instead, -gnatc (Check syntax and semantics only (no code
generation)) is used (bound to C-c C-v), and is extremely effective.