[Info-vax] Rust as a HS language, was: Re: Quiet?

[Arne Vajhøj]

On 4/4/2022 9:21 PM, Dave Froble wrote:
> On 4/4/2022 2:37 PM, Arne Vajhøj wrote:
>> On 4/4/2022 1:56 PM, Simon Clubley wrote:
>>> On 2022-04-04, Arne Vajhøj <arne at vajhoej.dk> wrote:
>>>> On 4/4/2022 8:28 AM, Simon Clubley wrote:
>>>>> 2) No official ISO or similar language standard I can rely on 
>>>>> 5/10/20 years
>>>>> from now when I need to work on my safety or general production 
>>>>> critical
>>>>> code at that point.
>>>>>
>>>>> Even though many of the Rust people appear not to understand this, the
>>>>> lack of those guarantees is a _massive_ problem in the real world.
>>>>
>>>> Not really. Lot of popular languages are not formally standardized.
>>>> Python and PHP are not standardized. C# is/was standardized but the
>>>> standard is 6 versions behind. It took 13 years before C++ got
>>>> standardized.
>>>
>>> You have just made my point for me Arne. Or to put it another way,
>>> Python 2 to Python 3.
>>>
>>> Why wasn't Python 3 just another language mode in the existing compiler
>>> instead of being a whole different compiler ?
>>
>> (ignoring that I would not call Python a compiler)
>>
>> The language has evolved. Most languages does.
> 
> There is "evolve", and there is "replace" ...

We are talking evolve here. Replace is different.

>> They could have chosen to prioritize backwards compatibility higher.
>> Let us call it "Java approach".
> 
> Or, the VMS approach.

Or the VMS Basic approach (to keep it around languages).

>> They could have introduced a compatibility mode. Let us call it
>> "DEC C approach".
>>
>> But they did not.
>>
>> Would difference decisions have been made if it had been an ISO
>> committee and not a BDFL?
>>
>> I don't know.
> 
> I'm pretty sure that a committee of people already using the product 
> would not allow a break such Python 2 to Python 3.  That is the 
> difference, and it is a major difference.

>> If the same people were making the decision then they may likely have
>> made the same decision. Whether they have a "core team" hat or an
>> "ISO WG member" hat should not change their opinion.
> 
> Oh, but it does.  When the developers are determined to do as they 
> please, and are not encumbered by users who might be affected, then you 
> have the Python issue.  It can happen anywhere when there is not user 
> input to decisions.

I do not believe that "ISO WG = end user influence" and "Core team = no
end user influence".

>>> I can compile C89 code on a compiler 33 years later. When another 
>>> standard
>>> for C is released, it becomes just another language mode in the existing
>>> compilers and all the existing C standards are still supported.
>>
>> That is a choice. They can change it if they want to.
>>
>>> How confident are you that I can compile C89 code in yet another 10 
>>> years ?
>>
>> Compatibility seems to be a priority so that seems extremely likely.
>>
>>> In comparison, how confident are you that I can compile existing 
>>> Python 3
>>> or Rust code in another 10 years ?
>>
>> Python - pretty sure. I believe the Python community learned the
>> lesson. Nobody expects an incompatible Python 4.
> 
> "Faith".  Something not dependent on reality or facts.

The fact is that any language can decide to make a breaking
change.

The only difference is how likely one consider it.

Arne