Help with Template Code

Jarrett Billingsley kb3ctd2 at yahoo.com
Sun Apr 1 10:40:37 PDT 2007


"Max Samukha" <samukha at voliacable.com> wrote in message 
news:nmmv03h5g5mtbkn6hetbnu33ei6nnnhd67 at 4ax.com...
> I thought it should, too. But when tested on Windows with dmd 1.010,
> the tuple version is significantly slower. I'm still not sure why.

Ahh, looking at the disassembly it makes sense now.  What happens is that 
when you write:

foreach(i, arg; args)
    t.tupleof[i] = arg;

It gets turned into something like _this_:

typeof(args[0]) arg0 = args[0];
t.tupleof[0] = arg0;
typeof(args[1]) arg1 = args[1];
t.tupleof[1] = arg1;
typeof(args[2]) arg2 = args[2];
t.tupleof[2] = arg2;

Notice it copies the argument value into a temp variable, then that temp 
variable into the struct.  Very inefficient.

Unfortunately I don't know of any way to get around this..  I was hoping

t.tupleof[] = args[];

would work, but it's illegal.

A static for loop would be nice. 




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