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digitalmars.D.learn - Can you move a disabled this struct in to a container type if it's an

reply aliak <something something.com> writes:
Ie:

struct S {
      disable this();
     this(int i) {}
}

struct Container(T) {
     T value;
     this(auto ref T value) {
         this.value = value;
     }
}

void main() {
     auto a = Container!S(S(3)); // can't do this.
}

I can build a custom constructor for Container that makes this 
work:

static auto construct(Args...)(auto ref Args args) {
     import std.algorithm: move;
     auto value = T(args);
     auto opt = Container!T.init;
     opt.value = move(value);
     return move(opt);
}

But is there a way to do it without adding a custom constructor 
type?

Cheers,
- Ali
Dec 12 2018
parent reply Paul Backus <snarwin gmail.com> writes:
On Wednesday, 12 December 2018 at 20:05:18 UTC, aliak wrote:

 Ie:

 struct S {
      disable this();
     this(int i) {}
 }

 struct Container(T) {
     T value;
     this(auto ref T value) {
         this.value = value;
     }
 }

 void main() {
     auto a = Container!S(S(3)); // can't do this.
 }


The only error I get when I compile this has to do with incorrect 
use of `auto ref`. If I change the constructor's signature to 
`this()(auto ref T value)`, it works fine.
Dec 12 2018
parent aliak <something something.com> writes:
On Wednesday, 12 December 2018 at 21:11:38 UTC, Paul Backus wrote:

 On Wednesday, 12 December 2018 at 20:05:18 UTC, aliak wrote:

 Ie:

 struct S {
      disable this();
     this(int i) {}
 }

 struct Container(T) {
     T value;
     this(auto ref T value) {
         this.value = value;
     }
 }

 void main() {
     auto a = Container!S(S(3)); // can't do this.
 }


 The only error I get when I compile this has to do with 
 incorrect use of `auto ref`. If I change the constructor's 
 signature to `this()(auto ref T value)`, it works fine.


Crap! So sorry, this was supposed to be this(this) and that auto 
ref is not supposed to be there :(

Posted new (and correct) message: 
https://forum.dlang.org/thread/sasdsmxmikxqfxhtbpyo forum.dlang.org
Dec 13 2018