From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-0.9 required=5.0 tests=BAYES_00,FORGED_GMAIL_RCVD,
	FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4
Path: 
 eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail
From: =?UTF-8?B?QmrDtnJuIEx1bmRpbg==?= <b.f.lundin@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: Build language with weak typing, then add scaffolding later to
 strengthen it?
Date: Fri, 29 May 2015 12:56:06 +0200
Organization: A noiseless patient Spider
Message-ID: <mk9ggb$8d0$1@dont-email.me>
References: <mjlale$dpk$1@speranza.aioe.org>
	<127b004d-2163-477b-9209-49d30d2da5e1@googlegroups.com>
	<mjn90s$9av$1@dont-email.me>
	<f89a678a-f4a3-4a1c-91d7-d465177bbb1d@googlegroups.com>
	<mjnieh$ejn$1@dont-email.me>
	<ad8483c7-8f3c-4469-9079-a97ca3abaf27@googlegroups.com>
	<mjnpkt$b6j$1@dont-email.me>
	<59a4ee45-23fb-4b0e-905c-cc16ce46b5f6@googlegroups.com>
	<mjo0mk$7qu$1@dont-email.me>
	<46b2dce1-2a1c-455d-b041-3a9d217e2c3f@googlegroups.com>
	<mjpsdi$6cq$1@dont-email.me>
	<ac78c8c6-de94-4f92-afcb-c1ae78523245@googlegroups.com>
	<mk85s3$uee$1@loke.gir.dk> <87a8wnu3v0.fsf@adaheads.sparre-andersen.dk>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
Injection-Date: Fri, 29 May 2015 10:54:03 +0000 (UTC)
Injection-Info: mx02.eternal-september.org;
 posting-host="d0b09246b18eaaefa6fe6aebe25eca1f";
	logging-data="8608"; mail-complaints-to="abuse@eternal-september.org";
	posting-account="U2FsdGVkX1/Qd7VE32F10oN6Tu1GAYLN"
User-Agent: Mozilla/5.0 (X11; Linux x86_64;
 rv:31.0) Gecko/20100101 Icedove/31.4.0
In-Reply-To: <87a8wnu3v0.fsf@adaheads.sparre-andersen.dk>
Cancel-Lock: sha1:0mQZ60JXN7YUN8oCsfZWyEtjby0=
Xref: news.eternal-september.org comp.lang.ada:26061
Date: 2015-05-29T12:56:06+02:00
List-Id: <comp.lang.ada>

On 2015-05-29 11:31, Jacob Sparre Andersen wrote:
> Randy Brukardt wrote:
> 
>> We don't. As with all old languages, it's political. We can't remove
>> old features (as that would break existing programs),
> 
> But aren't the existing programs being compiled with compilers for the
> appropriate (old) versions of the language?

Not necessarily.
Our system often has a life expectancy of 15 +- 5 years.
But the os/database/other tools does not.
Once say Oracle say - no support available - which they do relatively
fast - most customers wants a platform upgrade .
That is - make the same system run on a newer os/db/whatever.

And that includes a new Ada compiler.
Ans one really nice thing about Ada is that is usually
compiles and works right away.
If compiler-vendor-change took place, some fiddling is usually present,
but upgrading a system from one gnat to another is painless.

You get tons of more warnings - and that is it.

Another scenario is when a customer wants some 'newer' technology,
like webbish stuff.
To add AWS a relatively new compiler is needed.
And that should compile that rest of the system too - even if old.

> 
> How large is the actual benefit of maintaining practically full
> backwards compatibility?
> 

To us - very large.


> Isn't it more a matter of not being able to agree on what is important
> to keep, and what isn't?

If you ask around enough, you will likely get
answers that wants to keep 'odd' features.
I - for example - love the separate construct. we use it allot.
But I think not too many use it.


--
Björn