• Andrey Zherikov (25/25) Feb 17 2022 I have a struct that has struct data member and I'd like to
• Andrey Zherikov (6/8) Feb 17 2022 Actually the answer is `NO`. I have to do `auto foo(ARGS...)(auto
• Stanislav Blinov (9/17) Feb 18 2022 This also doesn't forward correctly. It'll always try to copy all

Andrey Zherikov <andrey.zherikov gmail.com> writes:

I have a struct that has struct data member and I'd like to 
forward some (not all) functions from internal data member. Some 
thing like this:
```d
struct A {
     void foo() const { writeln("A.foo"); }
}

struct B {
     A a;

     auto foo(ARGS...)(ARGS args) { return a.foo(args); }
     // alias foo = a.foo;
}

void main()
{
     B b;
     b.foo();   // In "alias" case: Error: `this` for `foo` needs 
to be type `A` not type `B`
}
```

Is there simpler way to achieve this?
I tried `alias foo = a.foo` but it doesn't work: "Error: `this` 
for `foo` needs to be type `A` not type `B`" - when function is 
called (`b.foo()`).

Another question: does `auto foo(ARGS...)(ARGS args) { return 
a.foo(args); }` correctly forward `ref`, `const` etc. arguments?

Andrey Zherikov <andrey.zherikov gmail.com> writes:

On Thursday, 17 February 2022 at 20:59:43 UTC, Andrey Zherikov 
wrote:
 Another question: does `auto foo(ARGS...)(ARGS args) { return 
 a.foo(args); }` correctly forward `ref`, `const` etc. arguments?

Actually the answer is `NO`. I have to do `auto foo(ARGS...)(auto 
ref ARGS args) { return
a.foo(args); }`. Also if `a.foo` is a `const` function then I 
have to add `const` to this definition as well.

Stanislav Blinov <stanislav.blinov gmail.com> writes:

On Thursday, 17 February 2022 at 21:17:02 UTC, Andrey Zherikov 
wrote:
 On Thursday, 17 February 2022 at 20:59:43 UTC, Andrey Zherikov 
 wrote:
 Another question: does `auto foo(ARGS...)(ARGS args) { return 
 a.foo(args); }` correctly forward `ref`, `const` etc. 
 arguments?

 Actually the answer is `NO`. I have to do `auto 
 foo(ARGS...)(auto ref ARGS args) { return
 a.foo(args); }`.

This also doesn't forward correctly. It'll always try to copy all 
arguments. What would fowrard is

```
import core.lifetime : forward;

auto foo(Args...)(auto ref Args args) { return 
a.foo(forward!args); }
```