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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: How to get Ada to "cross the chasm"?
Date: Fri, 4 May 2018 18:55:01 -0500
Organization: JSA Research & Innovation
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"Jere" <jhb.chat@gmail.com> wrote in message 
news:661b1ce8-f4e4-4a4b-9a07-ebe36d75f010@googlegroups.com...
...
>Basically, in Rust it forces you to use synchronization primitives
>on any variable being used in a thread (task equiv), which would be
>similar to if Ada required all variables in a thread to be protected
>types or fulfilled some other task safe context.

This is essentially what Ada 2020 is requiring(*) for parallel execution. 
(Tasks are of course unchanged for compatibility reasons, and one can turn 
off the checks for parallel execution if you think you know what you're 
doing.)

(*) This has changed a lot and it is still is mostly imaginary (little 
wording to date) so I surely hope this remains true. If not, I'll recommend 
delaying Ada 2020 until it is true, I don't see any point in yet another way 
to screw up with no compiler help.

The formal definition is that only subprograms that are globally 
synchronized and nonblocking can be called from a parallel construct. Both 
global synchronization and nonblocking are statically checked.


                        Randy.