Differences and comparison of advantages and disadvantages between C++ functions and macros

Functions are code blocks executed during runtime and can return results; macros are constants or code fragments expanded during preprocessing and cannot return results. Functions are easy to read, reusable, and have high code readability, but low efficiency; macro compilation has low overhead and excellent performance, but poor code readability and is difficult to debug.

The difference and advantages and disadvantages of C functions and macros

Overview of functions and macros

Function:Code A block that performs a specific task and returns a result.

Macro:The code name of a constant or other code fragment, which is expanded during the preprocessing stage.

Difference

Advantages and disadvantages

Function advantages:

• Easy to read and maintain
• Can return results
• High code reusability

Function disadvantages:

• Compilation overhead is large
• Performance is lower than macros

Advantages of macros:

• Compilation Minimal overhead
• Excellent performance

Macro disadvantages:

• Difficult to debug
• Code readable Poor performance
• Unable to return results

Actual case

The following is a code example for comparing functions and macros:

// 函数 int sum(int a, int b) { return a + b; } // 宏 #define SUM(a, b) (a + b) // 测试 int main() { int x = 10; int y = 20; int func_result = sum(x, y); // 函数调用 int macro_result = SUM(x, y); // 宏展开 std::cout << "Function result: " << func_result << std::endl; std::cout << "Macro result: " << macro_result << std::endl; return 0; }

Output:

Function result: 30 Macro result: 30

Conclusion

Functions and macros are useful tools for code reuse. Functions are more suitable for scenarios that require return values, type checking, and high code readability. Macros are more suitable for scenarios that require extremely high performance and compilation efficiency.

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