[BUG] error: local variable not used after using declaration but in fact it is

[wolfseifert]

After pulling in 510eae8:

prntln: (s: ::std::string) = {
  using ::std;
  cout << "A: (s)$" << endl;
}

does not transpile

inherit.cpp2(1,10): error: local variable 's' is not used; consider changing its name to '_' to make it explicitly anonymous, or removing it entirely if its side effects are not needed

[Herb Sutter]

Thanks!
@JohelEGP could you take a look at this?