Modern C++ for Absolute Beginners: A Friendly Introduction to C++ Programming Language and C++11 to C++20 Standards

© Slobodan Dmitrović 2020

S. DmitrovićModern C++ for Absolute Beginnershttps://doi.org/10.1007/978-1-4842-6047-0_21

21. Scope and Lifetime

Slobodan Dmitrović¹ 

(1)

Belgrade, Serbia

 

When we declare a variable, its name is valid only inside some sections of the source code. And that section (part, portion, region) of the source code is called scope. It is the region of code in which the name can be accessed. There are different scopes:

21.1 Local Scope

When we declare a name inside a function, that name has a local scope. Its scope starts from the point of declaration till the end of the function block marked with }.

Example:

void myfunction()

{

    int x = 123; // Here begins the x's scope

} // and here it ends

Our variable x is declared inside a myfunction() ...