struct vs class benchmark (was Re: Give struct the status it

[Ben Phillips]

Basically what your benchmark (along with Hong's) prove is that classes and
structs each have different uses (duh!). Use structs in situations like Hong's
case where classes would require a ton of allocation, and use classes in
situations like your case where passing by value would induce enormous overhead
costs.

In article <e09vl7$2u5f$1 at digitaldaemon.com>, Hasan Aljudy says...
>
>Derek Parnell wrote:
>> Classes are slower than structs. Prove otherwise. I'm happy to be shown  
>> that I'm wrong.
>> 
>
>Here's a slightly modified version of Dave's code.
>
>-------
>import std.stdio, std.date;
>
>struct S
>{
>	char[10000] str;
>}
>
>class C
>{
>	char[10000] str;
>}
>
>void main()
>{
>	const int y = 1_000_000_0;
>	
>	//structs
>	{
>		S s;
>		d_time st = getUTCtime();
>		for(int x = 0; x < y; x++)
>		{
>			fooS(s);
>		}
>		d_time en = getUTCtime();
>		writef("struct: ");
>		writefln((en-st) / cast(double)TicksPerSecond);
>	}
>		
>	//classes
>	{
>		C c = new C;
>		d_time st = getUTCtime();
>		for(int x = 0; x < y; x++)
>		{
>			fooC(c);
>		}
>		d_time en = getUTCtime();
>		writef("class: ");
>		writefln((en-st) / cast(double)TicksPerSecond);
>	}
>}
>
>void fooS(S s)
>{
>	s.str[9999] = 15;
>}
>
>void fooC(C c)
>{
>	c.str[9999] = 15;
>}
>----------
>
>on my machine:
>C:\test\d\struct.vs.class\pass>dave
>struct: 44.422
>class: 0.046
>
>that's about 1000 times faster
>
>44.422/.046 = 965.696
>
>Note: I don't believe this to be a valid benchmark, but I believe it's 
>just as valid as Hong's benchmark.
>
>It's designed to make the class version win.
>
>