Restrictions on overloaded functions (C++ only)

You cannot overload the following function declarations if they appear in the same scope. Note that this list applies only to explicitly declared functions and those that have been introduced through using declarations:

Function declarations that differ only by return type. For example, you cannot declare the following declarations:
```
int f();
float f();
```
Member function declarations that have the same name and the same parameter types, but one of these declarations is a static member function declaration. For example, you cannot declare the following two member function declarations of f():
```
struct A {
  static int f();
  int f();
};
```
Member function template declarations that have the same name, the same parameter types, and the same template parameter lists, but one of these declarations is a static template member function declaration.
Function declarations that have equivalent parameter declarations. These declarations are not allowed because they would be declaring the same function.
Function declarations with parameters that differ only by the use of typedef names that represent the same type. Note that a typedef is a synonym for another type, not a separate type. For example, the following two declarations of f() are declarations of the same function:
```
typedef int I;
void f(float, int);
void f(float, I);
```
Function declarations with parameters that differ only because one is a pointer and the other is an array. For example, the following are declarations of the same function:
```
f(char*);
f(char[10]);
```
The first array dimension is insignificant when differentiating parameters; all other array dimensions are significant. For example, the following are declarations of the same function:
```
g(char(*)[20]);
g(char[5][20]);
```
The following two declarations are not equivalent:
```
g(char(*)[20]);
g(char(*)[40]);
```
Function declarations with parameters that differ only because one is a function type and the other is a pointer to a function of the same type. For example, the following are declarations of the same function:
```
void f(int(float));
void f(int (*)(float));
```
Function declarations with parameters that differ only because of cv-qualifiers const, volatile, and restrict. This restriction only applies if any of these qualifiers appears at the outermost level of a parameter type specification. For example, the following are declarations of the same function:
```
int f(int);
int f(const int);
int f(volatile int);
```
Note that you can differentiate parameters with const, volatile and restrict qualifiers if you apply them within a parameter type specification. For example, the following declarations are not equivalent because const and volatile qualify int, rather than *, and thus are not at the outermost level of the parameter type specification.
```
void g(int*);
void g(const int*);
void g(volatile int*);
```
The following declarations are also not equivalent:
```
void g(float&);
void g(const float&);
void g(volatile float&);
```
Function declarations with parameters that differ only because their default arguments differ. For example, the following are declarations of the same function:
```
void f(int);
void f(int i = 10);
```
Multiple functions with extern "C" language-linkage and the same name, regardless of whether their parameter lists are different.

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