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From: "Alejandro R. Mosteo" <alejandro@mosteo.com>
Newsgroups: comp.lang.ada
Subject: Re: Microsoft is considering moving to Rust; potential opportunity
 for Ada2020
Date: Tue, 6 Aug 2019 19:01:12 +0200
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Date: 2019-08-06T19:01:12+02:00
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On 20/7/19 0:07, Simon Wright wrote:
> Paul Rubin <no.email@nospam.invalid> writes:
> 
>> Optikos <optikos@verizon.net> writes:
>>> Yes, I also was wondering why Microsoft isn't fervently exploring
>>> adding a Rust-esque borrow checker to C#
>>
>> C# is garbage collected, I thought.  No need for anything like a
>> borrow checker.
> 
> GC is about safely disposing of memory that's no longer accessible from
> anywhere in the program.
> 
> Borrow checking (AIUI) is about making sure that only one part of the
> program has write access to a particular piece of memory at once.

Yes and no. If you check the first chapters in the Rust tutorial, heap 
memory reclamation is also performed deterministically when the borrow 
checker determines some memory has no more references left pointing to it.

I've seen it described as static GC. I guess it's a side-effect of the 
borrow checker; if you have to know how many mutable/immutable references 
exist to a block of memory, you end knowing when none are left.

That's my superficial understanding (haven't done any serious Rust). I'm 
frankly impressed by the concept. It seems to be a real contribution to 
the general landscape. Too bad the syntax gets ugly pretty quickly; I 
wonder about long-term maintainability.

Also, the particular interest of Microsoft in Rust is clear to me; it 
precludes whole classes of memory errors that make for a big chunk of 
security vulnerabilities.