On 2011-06-12 15:08, Andrej Mitrovic wrote: > This seems like a way to simulate namespaces in C++, right? I wouldn't > know, but it looks similar to that 'using foo' trick.
C++ namespaces are completely different. Everything in a namespace has to be referenced by its namespace explicitly unless you use using. So, without using, you need to do stuff like std::vector<int> v; whereas with using namespace std; vector<int> v; you don't need the std:: tag anymore. Using namespace affects _everything_ after it, which is why it's pretty much verboten in header files (otherwise it would pollute the global namespace). And whether you have a using statement or not, as soon as you #include a file, everything in it is visible in the current file. Namespaces just segregate the names so that they don't clash. D modules are very different. As soon as you import a module, everything in that module is visible (though you can't use anything in it unless it's public or the current module is in the same package and it's package or if you're deriving from class in that module and the symbol in question is protected). You don't have to use the module name when using _any_ of its symbols unless names clash or you imported the module statically. It's kind of like you automatically have a using statement all of the time, except that it's much more sophisticated and handles name clashes much better. By importing within a function, you're saying that only that function has access to the symbols within the module being imported. As for as the rest of the module is concerned, the imported module does not actually exist. You're restricting what can see it. So, I'm not quite sure what you mean by this simulating C++ namespaces. They both deal with how symbols are brought into and viewable in the current file, but they're very different. - Jonathan M Davis