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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Introductory Ada Programming Book
Date: Wed, 04 Jan 2017 15:15:13 +0000
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> On 2017-01-04 14:45, raph.amiard@gmail.com wrote:
>
>> Or do it Swift's way and use flow analysis to make use of an
>> uninitialized variable a compile time error.
>
> That is a bad idea. If uninitialized variable is an error then that
> must make the program illegal. If the program is still legal, then it
> is not an error.

Swift's way appears to be that *using* an uninitialized variable is an
error (provided that the compiler can detect it, of course).

GNAT has warnings about possible UBI, I think. And SPARK makes it an
error.