What does :: mean in c++
The meaning of::operator in C
In C, the ::operator is called the range resolution operator, and it has two main purposes:
1. Access members within the namespace
Namespace is a way of organizing code in C. If a class or function is defined within a namespace, you need to use the :: operator to access it. For example:
namespace my_namespace { int my_variable; } int main() { my_namespace::my_variable = 10; return 0; }
2. Access members in the global scope
The global scope is the root level of the namespace. If a class or function is defined in the global scope, you can also use the :: operator to access it. For example:
class MyClass { // ... }; int main() { ::MyClass my_object; // :: 表示MyClass在全局作用域中 return 0; }
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