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From: "Alejandro R. Mosteo" <alejandro@mosteo.com>
Newsgroups: comp.lang.ada
Subject: Re: Why are Ada compilers difficult to write ?
Date: Mon, 25 Jun 2018 10:51:53 +0200
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Xref: reader02.eternal-september.org comp.lang.ada:53291
Date: 2018-06-25T10:51:53+02:00
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On 23/06/2018 18:14, Shark8 wrote:
> On Saturday, June 23, 2018 at 6:44:41 AM UTC-6, Dan'l Miller wrote:
>> On Saturday, June 23, 2018 at 12:56:43 AM UTC-5, J-P. Rosen wrote:
>>> Le 22/06/2018 à 18:10, Simon Clubley a écrit :
>>>> 3.10.2 (according to Randy)
>>>>
>>>> Personally, I don't think it's something to be proud of however.
>>>>
>>>> When a language is used in the critical environments that Ada is used in,
>>>> it shouldn't have anything in it which is that difficult to understand.
>>>
>>> Well, it is an attempt at making pointers safer, and this is inherently
>>> difficult. Other languages didn't even try...
>>
>> Except Rust nowadays, and hopefully Ada2020 will catch up
> 
> SPARK is better than Rust in terms of safety/reliability; there was a [possible] proposed extension to SPARK to allow access-types in certain, controlled conditions that was shown to the ARG. (They asked that we not promulgate it, I think because they wanted to publish/present it for their academic career.)

It was just presented in Ada-Europe 2018, and they said that it was 
inspired by Rust borrowing rules.

What I find interesting about the Rust approach is that (perhaps by their 
C-fixing motivation) it addresses something that is not tackled by Ada 
attempts, so I find it curiously orthogonal. So having something similar 
in SPARK seems only logical.