C++ Template vs Macro: What's the Difference?

What is the difference between a C++ template and a macro?

C++ templates are a feature that allows functions and classes to operate with generic types, while macros are preprocessor directives that perform text substitution before compilation.

Can you give me an example of a template?

Sure! Here's a simple example of a template function:

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

This function can add two values of any type that supports the + operator.

And what about a macro example?

Here's an example of a macro:

#define SQUARE(x) ((x) * (x))

This macro calculates the square of a number by substituting the expression wherever SQUARE(x) is used.

When should I use templates instead of macros?

You should use templates when you need type safety and better debugging support, while macros are useful for simple text substitutions or conditional compilation.