• Patric (38/38) Aug 01 2016 struct Test{
• Steven Schveighoffer (4/6) Aug 01 2016 You want opAssign, not opOpAssign. opOpAssign is for things like +=.
• Patric (6/15) Aug 01 2016 Same thing:
• Mike Parker (3/22) Aug 01 2016 You've implemented opAssign incorrectly. See:
• Patric (3/12) Aug 01 2016 Sorry, silly me, forgot to remove the "string op" now its ok :)
• Mike Parker (2/18) Aug 01 2016 Well, you beat me to it :)
• Patric (5/14) Aug 01 2016 But still.
• Mike Parker (3/6) Aug 01 2016 No. It was working as expected. You never implemented opAssign,
• Patric (2/8) Aug 01 2016 Iep, I realized this by now. Thanks anyway :)

Patric <patric.dexheimer gmail.com> writes:

struct Test{
	int x;
	this(int v){
		x = v;
		writeln(x.to!string ~ " Created");
	}
	~this(){
		writeln(x.to!string ~ " Destroyed");
	}
	void opOpAssign(string op, Type)(ref Type s){
		x = s.x;
	}
}
void showme(Type)(ref Type t){
	writeln(t.x);
}
void main(){
	auto t = Test(1);
	auto t2 = Test(2);
	showme(t);
	showme(t2);
	t = t2;
}

Prints:
1 Created
2 Created
1
2
1 Destroyed
2 Destroyed
2 Destroyed

this line:
t = t2
Causes the dtor to be called.

Why?
I expected nothing to happen because "ref" its a simple pointer, 
right?
Or I am missing something here?

Steven Schveighoffer <schveiguy yahoo.com> writes:

On 8/1/16 12:01 PM, Patric wrote:

 I expected nothing to happen because "ref" its a simple pointer, right?
 Or I am missing something here?

You want opAssign, not opOpAssign. opOpAssign is for things like +=.

Your code had me worried for a while :)

-Steve

Patric <patric.dexheimer gmail.com> writes:

On Monday, 1 August 2016 at 16:05:51 UTC, Steven Schveighoffer 
wrote:
 On 8/1/16 12:01 PM, Patric wrote:

 I expected nothing to happen because "ref" its a simple 
 pointer, right?
 Or I am missing something here?

 You want opAssign, not opOpAssign. opOpAssign is for things 
 like +=.

 Your code had me worried for a while :)

 -Steve

Same thing:
(Remembered now of DPaste)
(and I understand your concern :P)
https://dpaste.dzfl.pl/af512b5f6288

Mike Parker <aldacron gmail.com> writes:

On Monday, 1 August 2016 at 16:14:31 UTC, Patric wrote:
 On Monday, 1 August 2016 at 16:05:51 UTC, Steven Schveighoffer 
 wrote:
 On 8/1/16 12:01 PM, Patric wrote:

 I expected nothing to happen because "ref" its a simple 
 pointer, right?
 Or I am missing something here?

 You want opAssign, not opOpAssign. opOpAssign is for things 
 like +=.

 Your code had me worried for a while :)

 -Steve

 Same thing:
 (Remembered now of DPaste)
 (and I understand your concern :P)
 https://dpaste.dzfl.pl/af512b5f6288

You've implemented opAssign incorrectly. See:

https://dlang.org/spec/operatoroverloading.html#assignment

Patric <patric.dexheimer gmail.com> writes:

On Monday, 1 August 2016 at 16:05:51 UTC, Steven Schveighoffer 
wrote:
 On 8/1/16 12:01 PM, Patric wrote:

 I expected nothing to happen because "ref" its a simple 
 pointer, right?
 Or I am missing something here?

 You want opAssign, not opOpAssign. opOpAssign is for things 
 like +=.

 Your code had me worried for a while :)

 -Steve

Sorry, silly me, forgot to remove the "string op" now its ok :)

Mike Parker <aldacron gmail.com> writes:

On Monday, 1 August 2016 at 16:17:02 UTC, Patric wrote:
 On Monday, 1 August 2016 at 16:05:51 UTC, Steven Schveighoffer 
 wrote:
 On 8/1/16 12:01 PM, Patric wrote:

 I expected nothing to happen because "ref" its a simple 
 pointer, right?
 Or I am missing something here?

 You want opAssign, not opOpAssign. opOpAssign is for things 
 like +=.

 Your code had me worried for a while :)

 -Steve

 Sorry, silly me, forgot to remove the "string op" now its ok :)

Well, you beat me to it  :)

Patric <patric.dexheimer gmail.com> writes:

On Monday, 1 August 2016 at 16:05:51 UTC, Steven Schveighoffer 
wrote:
 On 8/1/16 12:01 PM, Patric wrote:

 I expected nothing to happen because "ref" its a simple 
 pointer, right?
 Or I am missing something here?

 You want opAssign, not opOpAssign. opOpAssign is for things 
 like +=.

 Your code had me worried for a while :)

 -Steve

But still.
If it was the case of "+=" wasn´t wrong to call the dtor since is 
a ref var?

Mike Parker <aldacron gmail.com> writes:

On Monday, 1 August 2016 at 16:18:32 UTC, Patric wrote:

 But still.
 If it was the case of "+=" wasn´t wrong to call the dtor since 
 is a ref var?

No. It was working as expected. You never implemented opAssign, 
so default assignment was being used. There was no ref variable.

Patric <patric.dexheimer gmail.com> writes:

On Monday, 1 August 2016 at 16:21:16 UTC, Mike Parker wrote:
 On Monday, 1 August 2016 at 16:18:32 UTC, Patric wrote:

 But still.
 If it was the case of "+=" wasn´t wrong to call the dtor since 
 is a ref var?

 No. It was working as expected. You never implemented opAssign, 
 so default assignment was being used. There was no ref variable.

Iep, I realized this by now. Thanks anyway :)