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You can hide a global variable like any other variable in a scope; you simply declare a new variable with the same name. That’s exactly what I do next, when I call hide_global(). The key line in that function doesn’t change the global variable glob; instead, it creates a new variable named glob, local to hide_global(), that hides the global variable.
int glob = 0; // hide global variable glob
As a result, when I send glob to cout next in hide_global() with the following line, 0 is displayed.
cout << "In hide_global() glob is: " << glob << "\n\n";
The global variable glob remains hidden in the scope of hide_global() until the function ends.
To prove that the global variable was only hidden and not changed, next I display glob back in main() with:
cout << "In main() glob is: " << glob << "\n\n";
Once again, 10 is displayed.
Tra p
Although you can declare variables in a function with the same name as a global variable, it’s not a good idea because it can lead to confusion.
