[Patch] Second half of tr1/complex

[Paolo Carlini]

Paolo Carlini wrote:

>I can trust you, but I want to understand in detail. Isn't true that
>'arg' is a reserved name? Otherwise, if the user can use 'arg' in any
>way, then do 'using ...arg', conflicts are always going to occur, one
>way, or another.
>  
>
To be clear, at the risk of appearing utterly naive, what's the
difference between breaking the hypothetical user code that you showed
and this one:

//#include <cmath>

//using std::sin;

int sin(double) { return 1; }

int main()
{
  int i = sin(2.0);
}

?!?

Paolo.