Head Const

[Andrei Alexandrescu via Digitalmars-d]

On 02/16/2016 09:44 PM, Walter Bright wrote:
> On 2/16/2016 5:35 AM, Dicebot wrote:
>> In my opinion @mutable would be a disaster of much higher destructive
>> impact than head const. I am very opposed to it no matter how it is
>> designed. Once you start considering it, you are better at simply
>> throwing away existing const system and starting it all from scratch
>> with D3. Logical const is harmful as it doesn't give and serious
>> guarantees but gives developer a false sense of confidence.
>
>
> I agree with you on that, and I've argued from that position before.
>
> Note that head const does not introduce any watering down nor
> destruction of the const/immutable/sharing type system. The main
> downside of head const would be language complexity.

I profoundly oppose such an outlook. It has a name - prejudice, pure and 
simple. Rejecting possible future ideas "no matter what" even before 
they exist is extremely damaging.

Consider:

"I oppose implicit narrowing conversions regardless how they are designed"

"static if is fundamentally flawed"

"Variadics cannot be both simple and safe"

etc.


Andrei