DIP25/DIP1000: My thoughts round 2

[Patrick Schluter]

On Wednesday, 5 September 2018 at 01:06:47 UTC, Paul Backus wrote:
> On Tuesday, 4 September 2018 at 16:36:20 UTC, Nick Treleaven 
> wrote:
>> My syntax for parameters that may get aliased to another 
>> parameter is to write the parameter number that may escape it 
>> in its scope attribute:
>>
>> On Sunday, 2 September 2018 at 05:14:58 UTC, Chris M. wrote:
>>> void betty(ref scope int*'a r, scope int*'a p) // okay it's 
>>> not pretty
>>
>> void betty(ref scope int* r, scope(1) int* p);
>>
>> p is documented as (possibly) escaped in parameter 1.
>
> Would using parameter names instead of numbers work? As an 
> unfamiliar reader, it wouldn't be clear at all to me what 
> `scope(1)` meant, but `scope(r) int* p` would at least suggest 
> that there's some connection between `p` and `r`.

It's indeed imho better as numbered parameters are a pita. Any 
change is annoying and fragile. I cannot count how often in C I 
had issues with annotations like __attribute__((nonnnul(5,9))) 
and __attribute__((format(printf, 3, 4))) when I had to change 
the parameters.