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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Why are Ada compilers difficult to write ?
Date: Fri, 29 Jun 2018 16:43:48 -0500
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Date: 2018-06-29T16:43:48-05:00
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"Dan'l Miller" <optikos@verizon.net> wrote in message 
news:2d287ba3-209d-4d6a-af79-77177a137885@googlegroups.com...
...
>Well, in an alternate universe, there would be a way to accomplish
>those declarations of constants or variables in the same package as
>their subtypes.

Surely.

But Ada 83 had a goal that Ada text would be processed linearly. It didn't 
quite achieve that (see visibility of goto labels), but it's close. This 
goal has been preserved in all more recent revisions of the language.

This goal wasn't adopted to make it easier to write compilers (although it 
sometimes has that effect), but rather to make it easier to *read* Ada code 
(ease of reading being one of Ada's primary goals). In general, you don't 
have to read anything following a declaration to determine how it will be 
implemented and execute.

                                              Randy.