Overview Why do we need the copy-and-swap idiom? Any class that manages a resource (a wrapper, like a smart pointer) needs to implement The Big Three. While the goals and implementation of the copy-constructor and destructor are straightforward, the copy-assignment operator is arguably the most nuanced and difficult. How should it be done? What pitfalls … Read more
Common operators to overload Most of the work in overloading operators is boiler-plate code. That is little wonder, since operators are merely syntactic sugar, their actual work could be done by (and often is forwarded to) plain functions. But it is important that you get this boiler-plate code right. If you fail, either your operator’s … Read more
Introduction C++ treats variables of user-defined types with value semantics. This means that objects are implicitly copied in various contexts, and we should understand what “copying an object” actually means. Let us consider a simple example: class person { std::string name; int age; public: person(const std::string& name, int age) : name(name), age(age) { } }; … Read more
static_cast is the first cast you should attempt to use. It does things like implicit conversions between types (such as int to float, or pointer to void*), and it can also call explicit conversion functions (or implicit ones). In many cases, explicitly stating static_cast isn’t necessary, but it’s important to note that the T(something) syntax … Read more
Why is “using namespace std;” considered bad practice?
The compiler is allowed to make one implicit conversion to resolve the parameters to a function. What this means is that the compiler can use constructors callable with a single parameter to convert from one type to another in order to get the right type for a parameter. Here’s an example class with a constructor … Read more
What are the differences between a pointer variable and a reference variable in C++?
Beginner Introductory, no previous programming experience Book Author(s) Description review C++ Primer* * Not to be confused with C++ Primer Plus (Stephen Prata), with a significantly less favorable review. Stanley Lippman, Josée Lajoie, and Barbara E. Moo (updated for C++11) Coming at 1k pages, this is a very thorough introduction into C++ that covers just … Read more