I'm writing some R functions that employ some useful functions in other packages like stringr and base64enc. Is it good not to call library(...) or require(...) to load these packages first but to use :: to directly refer to the function I need,…
Case 1
class Program {
static final int var;
static {
Program.var = 8; // Compilation error
}
public static void main(String[] args) {
int i;
i = Program.var;
System.out.println(Program.var);
…
I've got a name clash between two different Haskell modules that want to use the same infix operator (<*>). The Haskell 98 report says that
modid.varsym
is permitted, but I can't get it to work. In their entirety here are Test.hs:
module…
MSVC, Clang and GCC disagree on this code:
struct Base { int x; };
struct Der1 : public Base {};
struct Der2 : public Base {};
struct AllDer : public Der1, public Der2 {
void foo() {
Der1::Base::x = 5;
}
};
Godbolt
GCC:
:…
This question got me wondering whether it is ever useful/necessary to fully qualify class names (including the global scope operator) in an out-of-class member function definition.
On the one hand, I've never seen this done before (and the syntax to…
In Haskell, I can import a module qualified by its name or a shortcut name, like so:
import qualified Data.List as List
import qualified Data.Map
I can also import only a select set of functions from a module, or import all functions other than a…
The teacher in our programming lessons is talking about "unqualified names", but I'm wondering what they really are.
I suspect that things such as method names are unqualified, but I'm not certain.
Is there anyone who can explain this to me? I need…
It's not allowed to put a namespace and a class with the same name into one declarative region, i.e.
namespace A {}
class A{};
is ill-formed (see §3.3.1/4). However, one can introduce the name of either one via a using-directive:
namespace N {…
This code is accepted by MSVC9.0. My question is whether it is legal according to the standard (the old and/or the new one). A quote would be very much welcome, too.
class X
{
void X::f();
};
Recently, I've noticed, it is possible to have:
class Test {
public enum Season { WINTER, SPRING, SUMMER, FALL }
Season field = Season.WINTER.SPRING; // why is WINTER.SPRING possible?
}
Is there a reason for this?
The following namespace definition fails to compile when the first declaration is commented out. If the first declaration of foo is uncommented, then it compiles just fine.
namespace Y
{
//void foo();
void ::Y::foo(){}
}
The relevant part…
After reading MSDN-XAML Namespaces and MSDN-Understanding XAML Namespaces, I still do not understand the purpose of having a Qualified Name (QName).
Take the following namespace declaration as an…
When I use functions inherited from C, like the ones in or , should I qualify them as being part of the standard namespace std::log, or should I remain in the C-scope and use them as global functions? What about size_t?
This similar ill-fated question
got comments and short answers, before it was closed, to the effect: Because that's
how the language is defined. Here I am asking for the evidence within the
C++ Standard that it is so defined.
gcc 4.8.1 and clang 3.3…
