Jon Willesen wrote:
The only other thing I can think of that concerns me at all is if I'm trying to call a function that has been overloaded to take 1..N arguments using the preprocessor library or some other code generator. Then this code:
func(list_of<string>(), "foo", "bar", "baz");
might compile successfully and pass four arguments to func when I really meant to pass one argument:
func((list_of<string>(), "foo", "bar", "baz"));
Thorsten Ottosen wrote:
I think was the motivation. I had a user that called a constructor:
cons( list_of(3)(5), 4, 5 );
he wanted to pass 3 arguments, but only one was passed.
You got it backwards -- your example *does* pass three arguments. You have to add parentheses to only pass one: cons( (list_of(3)(5), 4, 5) );
Requiring paranthesis in certain contexts seems like a very subtle thing to do. I like easy syntax, but I also think surprising and subtle behavior can be a pain for users.
If you use the list_of comma syntax, surrounding parentheses are *always* required in every context. In most cases, forgetting the surrounding parentheses will result in a compile error. It doesn't seem so subtle to me; the consistency makes the rule easy to learn. -- Jon Willesen