Persistent list

[Timon Gehr via Digitalmars-d]

On 11/14/2015 09:42 PM, Andrei Alexandrescu wrote:
> On 11/14/2015 03:36 PM, Timon Gehr wrote:
>> Right, because e.g. whether the elements are reference counted or traced
>> should totally completely change the required container semantics for
>> the problem at hand! This does not make any sense, unless you are saying
>> that nobody should actually use the persistent containers, in which case
>> it seems like a waste of time to concentrate efforts on them.
>
> I'm just as weary of persistent containers of mutable elements using GC.
> It doesn't make a difference.
> ...

There must be a misunderstanding here. Fully mutable vs fully transitive 
immutable is a false dichotomy. I'm arguing for allowing at least the 
obviously valid use cases, you are arguing for disallowing at least the 
obviously wrong use cases.

>> You have not provided a technical argument, so I am going to assume you
>> have an irrational fear of bad PR. Forcing transitive immutable on
>> people who want persistent container semantics is ultimately a very poor
>> choice both from a technical and a PR perspective.
>
> The English language has a word I like a lot: "unassuming". I'm not sure
> about its etymology, but a nice theory is "a person who doesn't assume
> bad things about others".
> ...

Assuming this was the definition, your well-meaning intention cannot be 
to say that you assume that I am not entirely unassuming unless you 
consider it a good thing not to be unassuming. Anyway, I don't consider 
appeal to the assumed etymology of words to be a sound principle of 
reasoning.

In case that was unclear, I clearly did not mean to _assert_ that you in 
fact have this fear, as I have no way to know. I was just trying to 
probe what your reasoning was built on and possibly argue against it. 
Furthermore, it wouldn't necessarily be a bad thing.

> I'm glad to hear about various pros and cons regarding these  containers.

We have had the discussion you are asking for before, and you have 
decided to ignore it, with the justification that this was how you 
decided and a vague appeal to emotion. I usually don't operate under the 
assumption that identical experiments lead to different outcomes without 
a good reason.

> Slinging this kind of stuff

(I'm not slinging any kind of stuff.)

> is unlikely to further the dialog.
> ...

Maybe not, but what is? It can't be laying down a well-reasoned 
argument, because as recent history shows it will just be ignored 
without a reasonable justification.

I guess one other good way to proceed would be to just not have the 
dialog for now and instead wait until people who are actually trying to 
use the containers start complaining in blog posts and on reddit.

Feel free to voice any better suggestions you may have.