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From: "G.B." <bauhaus@notmyhomepage.invalid>
Newsgroups: comp.lang.ada
Subject: Safety of user-defined operators (was: Ada Successor Language)
Date: Sun, 3 Jun 2018 09:39:29 +0200
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Xref: reader02.eternal-september.org comp.lang.ada:52868
Date: 2018-06-03T09:39:29+02:00
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On 02.06.18 14:43, Dmitry A. Kazakov wrote:

> It is semantically problematic because it limits the implementation or forces a wrong implementation in case of temporal, volatile, shared objects. A special operator would allow implementation via proper procedure.
> 
> It is analogous to automatic dereferencing and indexing. There will be no solution to until these operations will be done via user-defined procedure. No number of kludges and obscure helper type will ever work. Assignment is no different.
> 

What set of guarantees can user-defined Ada offer, in comparison,
when users will provide those operations to the compiler that are
now guarandteed by the language? (Where to "draw the line"?)

Example:

- typed, indexed RAM (array),

as opposed to

- typed, indexed data structure (user defined).