UFCS - why only allow the first parameter?

[Jonathan M Davis]

On Saturday, February 23, 2013 08:26:57 dennis luehring wrote:
> func(a,b,c)
> 
> can be written as a.func(b,c)
> 
> is there a good reason
> 
> for not allwing
> 
> (a,b).func(c)
> 
> or even
> 
> (a,b,c).func()?
> 
> for me it feels natural

Because that's not what member functions look like. The whole point is to make 
calling the free function look as if it were a member function on the type of 
its first argument. In general, it shouldn't matter whether a function is a 
free function or a member function, it can be called the same way. That then 
makes the call syntax for functions "universal."

What you seem to be suggesting is to basically make it so that you can put the 
parens of the function call on either side of the function name, and that's 
not at all what UFCS is trying to do, and it doesn't help one whit with 
generic code, which is the primary benefit of UFCS.

- Jonathan M Davis