Help improve error message

[Salih Dincer]

On Saturday, 6 May 2023 at 20:02:30 UTC, ryuukk_ wrote:
> ...
> it's not what you expect..
>
> ```
> onlineapp.d(6): Error: none of the overloads of template 
> `object.get` are callable using argument types `!()(Something)`
> /dlang/dmd/linux/bin64/../../src/druntime/import/object.d(3442):        Candidates are: `get(K, V)(inout(V[K]) aa, K key, lazy inout(V) defaultValue)`
> /dlang/dmd/linux/bin64/../../src/druntime/import/object.d(3449):                        `get(K, V)(inout(V[K])* aa, K key, lazy inout(V) defaultValue)`
> ```
>
> There is the actual error message, surprising right?

The interesting thing is that we encountered this error in 
previous versions (eg. v2.087). It hasn't been tried in all 
versions, but I'm sure this error will appear at some version. I 
encountered this once as well.

Now I tried with the following code. Yes, even with the latest 
version I got the same error. However, DMD has such an advanced 
error and suggestion mechanism that it guides you how to use 
opAssign correctly.

```d
struct Something {
   void opAssign(int) {

   }
}

void main() {
      Something test;/* = 1; /*
      `test = 1` is the first assignment of `test` therefore it 
represents its initialization
      `opAssign` methods are not used for initialization, but for 
subsequent assignments//*/

       test = 1;/*
       // Error: no overload matches for `get`
       test.get();//*/
       writeln(__VERSION__*.001); // 2.087
}
```

SDB at 79