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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: In precision typing we trust
Date: Mon, 18 Aug 2025 13:08:32 +0200
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On 2025-08-18 12:29, Kevin Chadwick wrote:
> On LinkedIn Richard Riehle suggested that strong typing was claimed by many
> languages but Ada offers more in precision typing. I wonder if precision
> would fit around the coin?

These are unrelated issues. Strong typing is about:

1. Any object has a type. Note that many OO languages violate this 
principle, but not Ada which has T'Class and T separate.

2. Types have definite set of operations, arguments and results are 
typed. No, ellipsis, no messages (calling an operation on any object), 
no pattern matching of calls etc.

3. Types are insulated unless a relationship is explicitly stated by the 
programmer. E.g. no implicit type conversions.

What Richard refers to is an accuracy of mapping a type to the problem 
space. Talking about numerical entities the model types have precision, 
range, accuracy (float vs. fixed-point vs. unbounded), behavior like 
rounding, handling of exceptional states (breaking out the model) etc.

A counter example to Richard's statement. A weakly typed PL/1 had 
precision types.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de