Thank you!

[Steven Schveighoffer]

On 9/7/21 1:01 AM, Tejas wrote:
> On Tuesday, 7 September 2021 at 01:34:01 UTC, Basile B. wrote:
>> On Wednesday, 1 September 2021 at 04:40:37 UTC, Виталий Фадеев wrote:
>>> I want say "Thank you!" to all who works under D.
>>>
>>> I see the result of your work, even if it is small, even the size of 
>>> a byte.
>>> I use D and see your gift.
>>> I like. :)
>>
>> while this code looks natural and obvious, although pointless
>>
>> ```d
>> module m;
>>
>> struct S { int i; }
>>
>> S _s;
>>
>> S s (){return _s;}
>>
>> void main()
>> {
>>     s().i = 42;
>> }
>> ```
>>
>> the reality is that `i` can only be accessed through a pointer to a 
>> `S` (you want a deref of the address plus a offset).but `s` returns a 
>> `S` by value... so a temporary is created.
>>
>> All the time we write code that compiles but this code just compiles 
>> because the front end will help us, in this case, by turning `s()` 
>> into a lvalue.
>>
>> so we can indeed say thanks. what you think just works actually 
>> requires some unexpected rewrites, like **all the time**.
> 
> Don't you think it would be better to raise a warning though instead of 
> silently fixing it?
> 
> It would help people understand the differences between `structs` and 
> `classes` better, and when they will be using them in a much more 
> complex set of circumstances where the compiler won't be able to detect 
> what they're doing, they'll use them the right way.
> 
> This seems like setting them up for frustration in the future, since one 
> can definitely run into a case where `struct` will purely be treated as 
> a value type and then the user will feel that the behaviour is 
> inconsistent with what they've experienced.
> 
> 
> This reminds me of single length string literals being treated as a 
> character.
> 
> ```d
> void main(){
>       char[5] a = "y";//shouldn't compile, but it does

That is certainly an odd behavior. Looking at the resulting array, it's 
padded with 0s.

>       char[5] b = 'y';
>       writeln(a);
>       writeln(b);
> }
> 
> 
> Output:
> y
> yyyyy
> ```

This is not doing what you think it is doing. It's outputting 
essentially `"y\0\0\0\0"`, you just don't see the 0's on the console.

> 
> Was it a good thing that the compiler rewrote the string into a char in 
> this case? Wouldn't it be better if an error/warning was provided instead?

I think this "feature" should be removed, personally. Especially since 
it's not consistent with other array types.

-Steve