Question

form ISO Standard Draft

n3234 says:

Two names are the same if
— they are identifier s composed of the same character sequence, or

According to this meaning..Check whether this is correct or not

class ABC{};
class abc{};
int ABC(){}
int abc(){}
int main(){
           int abc;
           char ABC;
         }

is this program is correct according to the above statement?

is this program is APT to this statement?(what that statement meaning represents)

Finally ..explain any other thing ..is i left?

Answer 1

From ISO/IEC 14882:2003(E) 9.1.2 –

A class definition introduces the class name into the scope where it is defined and hides any class, object, function, or other declaration of that name in an enclosing scope (3.3). If a class name is declared in a scope where an object, function, or enumerator of the same name is also declared, then when both declara- tions are in scope, the class can be referred to only using an elaborated-type-specifier (3.4.4).

[Example:

struct stat { 
   // ...
};

stat gstat;    // use plain stat to 
               // define variable

int stat(struct stat*);   // redeclare stat as function

void f() {
    struct stat* ps; stat(ps);   // struct prefix needed 
                                 // to name struct stat 
                                 // ...
}

—end example]

3.3.7 Name hiding

2 A class name (9.1) or enumeration name (7.2) can be hidden by the name of an object, function, or enumer- ator declared in the same scope. If a class or enumeration name and an object, function, or enumerator are declared in the same scope (in any order) with the same name, the class or enumeration name is hidden wherever the object, function, or enumerator name is visible.

---

With the quotes from the standards, all these statements are correct.

class ABC{};
class abc{};   // abc and ABC are two different character sequences for the 
               // class entity. And similar is the case for next two function
               // entities.

int ABC(){} 
int abc(){}

int main(){      
    int abc;   // abc and ABC are two different character sequences.
    char ABC;
}

Finally ..explain any other thing ..is i left?

Both the functions ABC(), abc() are supposed to return int, which they are not doing though 🙂