C++ nullptr

🚫 C++ nullptr – The Modern Way to Say “No Address”

In C++, if a pointer doesn’t point anywhere, we say it’s null. Before C++11, we used NULL. But now we have something better — nullptr!

nullptr is a special keyword that means “this pointer points to nothing.”

🤔 Why use nullptr?

  • Type-safe – It’s only for pointers
  • Modern – Recommended since C++11
  • Prevents bugs – No accidental confusion with integers

🔧 Example: Using nullptr with Pointers

#include <iostream>
using namespace std;

void greet(int* p) {
    if (p == nullptr) {
        cout << "Pointer is null!" << endl;
    } else {
        cout << "Value: " << *p << endl;
    }
}

int main() {
    int* ptr = nullptr;
    greet(ptr);  // Will say "Pointer is null!"

    int x = 42;
    ptr = &x;
    greet(ptr);  // Will print the value

    return 0;
}

Try It Now

📌 nullptr vs NULL vs 0

  • NULL – Old C-style (actually just 0)
  • 0 – Dangerous, could be confused with int
  • nullptr – ✅ Modern and safe (best choice)

💡 Summary

  • nullptr represents a null (empty) pointer
  • Use it to avoid bugs and write modern C++
  • Always prefer nullptr over NULL or 0

So next time you want to say “this pointer goes nowhere,” say it like a pro — use nullptr! 🧠✨