I have a stupid question: how does D handle variable length argument lists? I've been over the D document and didn't see anything on it unless I missed something.

Thanks,
Ted

"Ted Williams" <ted.wil.no.spam@verizon.net> wrote in message news:c8llpv$tqc$1@digitaldaemon.com...
> I have a stupid question: how does D handle variable length argument
lists?
> I've been over the D document and didn't see anything on it unless I
missed
> something.

They work just like they do in C and C++.

Ted Williams schrieb:
> I have a stupid question: how does D handle variable length argument lists? I've been over the D document and didn't see anything on it unless I missed something.
> 
> Thanks,
> Ted
> 
> 

So I have a little Example here:

If the arguments are from the same type:

import std.stdio;

double add(double param[] ...) {
	double result = 0;
	foreach(double d; param) {
		result += d;
	}
	return result;
}

int main() {
	double zahl;
	zahl = add(2, 5.6, 7.8);
	writefln("%s", zahl);
	return 0;
}

This is a good example. ;) You call it typesafe.
;)

Or if there are different types of arguments:

import std.stdio;

int main() {
	double zahl = add(1, 5.6, 41, "Hello");
	writefln("%s", zahl);
	return 0;
}

double add(...) {
	double result = 0;
	for(int i=0; i < _arguments.length; i++) {
		if(_arguments[i] == typeid(double)) {
			double var = *cast(double*)_argptr;
			result += var;
			_argptr += double.sizeof;
		} else if(_arguments[i] == typeid(float)) {
			float var = *cast(float*)_argptr;
			result += var;
			_argptr += double.sizeof;
		} else if(_arguments[i] == typeid(int)) {
			int var = *cast(int*)_argptr;
			result += var;
			_argptr += int.sizeof;
		} else if(_arguments[i] == typeid(bool)) {
			_argptr += bool.sizeof;
		} else if(_arguments[i] == typeid(char[])) {
			char[] var = *cast(char[]*)_argptr;
			_argptr += var.sizeof;
		}
	}
	return result;
}

But you see: You have to read out the types of the arguments.
You can use: _arguments[] for the arguments.
But you have to do "_argptr += argumenttype.sizeof" because so you get
the beginning of the next argument.

Greetings Fabian Claßen

Reply to Fabian,

this thread is over 4 year old. most threads are in the digitalmars.d.* NG's