Pass by const reference

Syntax

void printName(const std::string& name)
{
	std::cout << name;
}

std::string name { "Ada" };
printName(name);

The reference refers to the caller’s object. const prevents the function from modifying that object through the parameter.

When to use it

• The object is required and must not be null
• Copying the object may be expensive
• The function only needs to read the object