Passing Arguments on in Variadic Functions

[jmh530 via Digitalmars-d-learn]

On Thursday, 17 September 2015 at 21:27:31 UTC, jmh530 wrote:
>

There's probably a way to clean this up better, but this is what 
I was talking about.

import std.algorithm : sum;
import std.stdio : writeln;
import std.traits : isNumeric;

auto test(T)(T x, bool sample=true)
{
	auto sum_x = sum(x);
	if (sample)
		return sum_x;
	else
		return sum_x / 2;
}

auto test(T, V ...)(T x, V y)
{
	static if (y.length)
	{
		static if (y.length == 2 &&
			   is(typeof(y[0]) == bool) &&
			   isNumeric!(typeof(y[1])))
		{
			auto sum_x = sum(x, y[1]);
			if (y[0])
				return sum_x;
			else
				return sum_x / 2;
		}
	}
}

void main()
{
	int[] x = [10, 5, 15, 20, 30];
	writeln(test(x, true));
	writeln(test(x, false));
	float seed = 1;
	writeln(test(x, true, seed));
	writeln(test(x, false, seed));
}