Can we deprecate "D-style Variadic Functions"

[Shammah Chancellor via Digitalmars-d]

On 2015-03-26 01:04:03 +0000, Freddy said:

> On Thursday, 26 March 2015 at 00:11:05 UTC, Dicebot wrote:
>> On Wednesday, 25 March 2015 at 22:12:04 UTC, Freddy wrote:
>>> "D-style Variadic Functions" found here:http://dlang.org/function.html 
>>> seem entirely out classed by Variadic Function Templates. Can we 
>>> deprecate them?
>> 
>> Those are two different concepts with different trade-offs. Using 
>> variadic templates adds template bloat. Using D-style variadics 
>> requires RTTI (and small overhead for it). It is up to 
>> library/application writer to decide what is best in his case.
> 
> My ploblem is that Variadic Function shouldn't be builtin the language. 
> They are rarely need and can be abstracted into a library. Something 
> like this:
> ```
> import core.stdc.stdlib: alloca;
> import std.stdio;
> template VariadicFunction(alias Imp){
> 	auto VariadicFunction(T...)(T args){
> 		enum size=T.length * TypeInfo.sizeof;
> 		auto rtti=cast(TypeInfo[])(alloca(size)[0..size]);
> 		foreach(i,type;T){
> 			rtti[i]=typeid(type);
> 		}
> 		//auto data=&args; bug? doesn't work
> 		void* data;
> 		{
> 			size_t datasize;//T.sizeof doesn't work
> 			foreach(type;T){
> 				datasize+=type.sizeof;
> 			}
> 			data=alloca(datasize);
> 			size_t inc;
> 			foreach(v;args){
> 				*cast(typeof(v)*)(data+inc)=v;
> 				inc+=v.sizeof;
> 			}
> 		}
> 		Imp(data,rtti);
> 	}
> }
> 
> private void rtVariadicImp(void* vars,scope const TypeInfo[] rtinfo){
> 	writeln(*cast(int*)vars);
> 	writeln(rtinfo);
> }
> 
> alias rtVariadic=VariadicFunction!(rtVariadicImp);
> 
> void main(){
> 	rtVariadic(1,'a');
> }
> ```

I disagree, and your example does not get rid of the template bloat.  
That does in fact instantiate a template for every set of argument 
types.

-Shammah