What are the advantages ans disadvantages of employing the

[kabaismael]

What are the advantages ans disadvantages of employing the "using"
directive?

[weaknessforcats]

C++ requires that all names must be unique. To avoid name clashes you place names inside namespaces:

int x;
 
namespace system
{
struct data
{
int a,b,c;
datat x;
}
namespace mystuff
{
double x;
}
 

These are three different variables with names of:

::x
system::x
mystuff::x

So far so good. Now let’s say you don’t like all this :: stuff in the variable name so you can tell the compiler to check a namespace for the variable name:

using namespace system;
 

Now instead of coding system::x all you need is x because you have told the compiler you are using namespace system.

x= 10;
 

However, this x might be ::x or system::x. If the x is ::x this code compiles. If the x is system::x, the code does not compile.

The using directive is for lazy programmers only. Top be safe you should always use fully qualified names in your