Omitting Namespace in C++

You can explicitly use the std:: prefix for standard library objects and functions instead of using the “using namespace std”.

Example of Omitting Namespace

Here’s a simple example to illustrate this −

#include <iostream>
#include <string>

int main() {
   std::string greeting = "Hello,TheMAK Pro Learner!";
   std::cout << greeting << std::endl;
   return 0;
}

In this example we had directly used std::string and std::count instead of using using namespace std;

When and Why to Omit Namespaces?

Omitting namespaces in C++ can be beneficial in several scenarios. Here we will discuss some key reasons and scenarios −

• Large projects − Using “using namespace std” in large codebases may create issues like naming conflicts, especially when working with multiple libraries and overlapping.
• Library Development − While creating libraries it is important to avoid “polluting global namespace” (which occurs when too many identifiers are declared in global namespace such as function, classes, variables etc) to prevent conflicts with other libraries. Using std:: helps avoid conflicts with other libraries or user-defined names which might have the same identifiers.
• Improved Readability and Better Maintenance − std:: makes it easier to track dependencies and to understand the origins of various functions and objects, which is helpful during debugging and maintenance.