auto*

[Meta via Digitalmars-d]

On Thursday, 6 July 2017 at 23:51:13 UTC, H. S. Teoh wrote:
> On Thu, Jul 06, 2017 at 11:50:24PM +0000, bauss via 
> Digitalmars-d wrote: [...]
>> Let's say you have.
>> 
>> auto a = foo();
>> 
>> You have no idea what auto actually is in that case, but
>> 
>> auto* a = foo();
>> 
>> You know auto is a pointer of whatever foo returns.
>
> Ah, I see.  So if foo() doesn't return a pointer it will be a 
> compile error?  So it's basically a kind of self-documentation?
>
>
> T

Kenji also extended the inference to some very interesting cases.

     // static array type
     int[$]   a1 = [1,2];    // int[2]
     auto[$]  a2 = [3,4,5];  // int[3]
     const[$] a3 = [6,7,8];  // const(int[3])

     // dynamic array type
     immutable[] a4 = [1,2];    // immutable(int)[]
     shared[]    a5 = [3,4,5];  // shared(int)[]
     // partially specified part is unqualified.

     // pointer type
     auto*  p1 = new int(3);  // int*
     const* p2 = new int(3);  // const(int)*

     // mixing
     auto[][$] x1 = [[1,2,3],[4,5]];  // int[][2]
     shared*[$] x2 = [new int(1), new int(2)];  // shared(int)*[2]

(https://github.com/dlang/dmd/pull/3615)

Of course this could also get confusing pretty fast. I wish we at 
least had the `int[$]` syntax but it's not a huge loss.