D1 operator overloads have been deprecated.

Bert Bert at gmail.com
Sun Jul 14 05:27:28 UTC 2019

On Friday, 12 July 2019 at 15:21:10 UTC, FeepingCreature wrote:
> On Friday, 12 July 2019 at 13:42:35 UTC, Bert wrote:
>> um, the OP said "works with virtual functions/inheritance". 
>> When are people going to learn that aliases are not virtual 
>> and have nothing to do with preserving inheritance structure?
> You're misunderstanding.
> import std.stdio;
> abstract class X
> {
>     abstract X opAddImpl(X rhs);
>     alias opBinary(string op:"+") = opAddImpl;
> }
> class C : X{
>     int x;
>     this(int x){ this.x=x; }
>     override C opAddImpl(X rhs){
>         return new C(x+(cast(C) rhs).x);
>     }
> }
> void main(){
>     X a=new C(1),b=new C(2);
>     writeln((cast(C) (a+b)).x);
> }

This works but now requires modifying the entire oop structure to 
conform. This is now how oop is suppose to work or good design 
decisions. We are talking about a pre-existing oop design that 
might be 100's of classes in size.

It's all fine and dandy when you are designing something from 
scratch but since D1 essentially does this anyways, what's the 
point of depreciating it then requiring it?


import std.stdio;

abstract class X
     //abstract X opNeg(); // D1
     abstract X opNegImpl(); // D2
     alias opUnary(string op : "-") = opNegImpl; // D2

class C : X
     int x;
     this(int x) { this.x = x; }
     //override C opNeg(){ return new C(-this.x); } D1
     override C opNegImpl() { return new C(-x); }


void main()
     X a = new C(1), b = new C(2);

So, all that has been achieved is allowing one to use their own 
base function names. A whole shit load of code is going to be 
broke SIMPLY to remove the default opXXX names... names that 
would rarely be used in any code for any other purpose 
anyways(I've never in my live used an id starting with op that 
was not meant to be used as an operator).

Absolutely nothing is achieved if the only issue is "there are 
"two" ways of doing it" as J.D. says.

In the new way we have to have an alias redirector and the 
function rather than just the function. All we end up getting is 
freeing a member id name and a whole lot of broken code.

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