How to copy object of class A to another object of class B?

[zhmt via Digitalmars-d-learn]

void getT(SRC,DEST)(SRC src,DEST dest)
{
	foreach (i, type; typeof(SRC.tupleof)) {
		string name = SRC.tupleof[i].stringof;
		__traits(getMember, dest, name) =  __traits(getMember, src, 
name);
  		writeln(name);
	}
}

when I write the code above, the compile complains that:

source/app.d(14): Error: variable name cannot be read at compile 
time.