The difference between C++ function overloading and function templates

The difference between function overloading and function templates: Function overloading: functions of the same domain with the same name but different input types and quantities. The corresponding function is selected according to the input type during compilation. Function template: A general function definition that uses type placeholders to generate specific functions based on the input type during instantiation.

The difference between C function overloading and function templates

Function overloading

• Function overloading means that there are multiple functions with the same name in the same scope, but their formal parameter types and numbers are different.
• When an overloaded function is called, the compiler will determine which function to call based on the type and number of parameters passed in.

Code example:

int add(int a, int b) {
  return a + b;
}

double add(double a, double b) {
  return a + b;
}

int main() {
  int result1 = add(1, 2); // 调用 int add()
  double result2 = add(1.5, 2.5); // 调用 double add()
  return 0;
}

Function template

• Function template is a general function Definition, which defines the skeleton of a function, including type placeholders for formal parameters.
• When instantiating a function template, the compiler will generate a specific function based on the type parameters passed in.

Code example:

template <typename T>
T add(T a, T b) {
  return a + b;
}

int main() {
  int result1 = add<int>(1, 2); // 实例化 int add()
  double result2 = add<double>(1.5, 2.5); // 实例化 double add()
  return 0;
}

Difference

• Function:Function Overloading is used to create functions with the same functionality but different input types, while function templates are used to create generic functions that can handle different types of data.
• Type processing: Function overloading handles specific types, while function templates handle type parameters.
• Efficiency: Function overloading is generally more efficient than function templates because the compiler only needs to select an existing function, whereas function templates require generating new functions upon instantiation.

The above is the detailed content of The difference between C++ function overloading and function templates. For more information, please follow other related articles on the PHP Chinese website!