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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: How to get Ada to "cross the chasm"?
Date: Sat, 05 May 2018 17:12:08 -0700
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Date: 2018-05-05T17:12:08-07:00
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Luke A. Guest <laguest@archeia.com> writes:
> I have to agree with this, this should be a high priority imo. Especially
> since everyone and their dogs are jumping on the Rust bandwagon, this could
> shut them up.

Is this something like C++ std::unique_ptr except the compiler is
supposed to enforce 1) you never call something like .get() which
extracts an unrestricted pointer, and 2) you can never use a unique_ptr
variable if you've transferred away the ownership with the equivalent of
std::move (ordinary assignment in the AI example)?  In C++ doing that is
a runtime error, which isn't ideal.

1) seems easy, 2) looks very useful but might have far-reaching
implications for the compiler type checker.  Would it need something
like Rust's affine types?  I don't know how they work but if Ada got
them, maybe they could be used in lots of other ways as well.