DIP1004: Inherited Constructors

[Arafel via Digitalmars-d-announce]

On Monday, 28 November 2016 at 02:38:00 UTC, Dicebot wrote:
> DIP 1004 is merged to the queue and open for public informal 
> feedback.
>
> PR: https://github.com/dlang/DIPs/pull/42
>
> Initial merged document: 
> https://github.com/dlang/DIPs/blob/master/DIPs/DIP1004.md
>
> If you want the change to be approved and have ideas how to 
> improve it to better match on 
> https://github.com/dlang/DIPs/blob/master/GUIDELINES.md and 
> existing published reviews - please submit new PR with 
> editorial and ping original author.

I think I might be a bit late to the party, and I'm still quite 
new in D... but wouldn't a variadic template constructor work? 
The usual rules of templates would still let you override a 
constructor if needed.

---
class A {
	this() { }
	this(int a) { }
}
class B : A {
	// Here we inherit all of A's constructors.
	this(Args...)(Args args) {
		super(args);
	}
	this(string s) { }
}
void main() {
	B b1 = new B(42);
	B b2 = new B("foo");
}
---

I've been playing with it, and the only problems I can see are 
with specialization and casting (i.e. B defines this(float), but 
you want to call A's this(int), the int will be promoted to float 
and B's version will be used). A way of disabling them would be 
needed, though... perhaps assert(0)?