C++ Core Guidelines

The C++ Core Guidelines are a set of best practices and design rules curated by Bjarne Stroustrup and Herb Sutter. Following them helps you write type-safe, resource-safe, and maintainable C++ code.

The Raw Pointer Rule: Non-Owning Observers Only

One of the most important rules in the guidelines is the ownership rule:

This means raw pointers should only be used to inspect objects, never to manage their lifetimes or delete them. This prevents double-free errors and memory leaks.

Code Walkthrough

Contrasts C-style resource management with modern, Core Guidelines-compliant code.

#include <iostream>
#include <memory>
#include <vector>
// BAD: Owning raw pointers can easily lead to memory leaks
void processBad() {
    int* data = new int[10];
    // If an exception is thrown here, the memory leaks
    delete[] data;
}
// GOOD: Safe, auto-managed container compliance
void processGood() {
    std::vector<int> data(10, 0); // Resource managed by vector RAII
}
// GOOD: Raw pointer used only as a non-owning observer
void printData(const int* val) {
    if (val) std::cout << *val << '\n';
}
int main() {
    auto val = std::make_unique<int>(42);
    printData(val.get()); // Pass raw pointer as non-owning observer
    return 0;
}

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