Pointers vs. References: When to Use Each in Function Parameters?

Pointers vs. References in Parameter Passing

Regarding pointers and references as function parameters, the code snippets provided do have functional similarities:

int foo(bar* p) {
  return p->someInt();
}

and

int foo(bar& r) {
  return r.someInt();
}

However, there are subtle differences between the two:

• Null Pointers: The pointer parameter allows for passing nullptr, while the reference parameter cannot be assigned nullptr.
• Optimizations: In certain cases, the compiler may optimize reference parameters over pointers, reducing overhead.

In C , references intentionally are not implemented explicitly with pointers. Instead, they serve as "synonyms" for the referenced variable. This concept enables compiler optimizations where pointers would be unnecessary.

Other notable differences between pointers and references include:

• Cannot Reassign: References cannot be reassigned, while pointers can.
• Address: Taking the address of a pointer returns the address of the pointer itself, while taking the address of a reference returns the address of the referenced object.

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