DIP: @mustuse as function return value annotation

[Richard (Rikki) Andrew Cattermole]

On 12/08/2024 8:35 PM, Richard (Rikki) Andrew Cattermole wrote:
> On 12/08/2024 8:29 PM, mw wrote:
>> On Monday, 12 August 2024 at 08:11:58 UTC, Richard (Rikki) Andrew 
>> Cattermole wrote:
>>> On 12/08/2024 8:09 PM, mw wrote:
>>>> I have no idea how the current D's compilation model works.
>>>>
>>>> To implement what is proposed above, I assume there is only one 
>>>> global ASTree (singleton) of all the source files (even in the 
>>>> context of separate compilation of each D source file), which holds 
>>>> all the calculated annotation from different compilation passes, and 
>>>> the @mustuse checker is invoked after all the annotations are fully 
>>>> calculated.
>>>
>>> That works for one process invocation.
>>>
>>> But D is multi-process invocation.
>>>
>>> A process is built by multiple compiler executions and do not share 
>>> this knowledge.
>>>
>>> This information simply wouldn't exist for later stages of compilation.
>>
>> Can we write the ASTree to temporary files, or a daemon process? so 
>> the calculated global annotation can be shared by later compilation 
>> process.
> 
> This has been discussed a lot of times in the past including for the 
> benefit to performance.
> 
> Also no, we cannot use a daemon process for this. The multiple compiler 
> invocations may not be on the same machine, or started by the same person.
> 
> Unfortunately the only option is to either disallow adding it to 
> classes, or disallow casting upwards, I am unaware of any other solution 
> to this.

Oh and you can also disallow overriding functions that don't have it, 
and then adding it. That'll also work!