Declaration A prototype for a function which takes a function parameter looks like the following: void func ( void (*f)(int) ); This states that the parameter f will be a pointer to a function which has a void return type and which takes a single int parameter. The following function (print) is an example of … Read more
Read it backwards (as driven by Clockwise/Spiral Rule): int* – pointer to int int const * – pointer to const int int * const – const pointer to int int const * const – const pointer to const int Now the first const can be on either side of the type so: const int * … Read more
The C standard defines the [] operator as follows: a[b] == *(a + b) Therefore a[5] will evaluate to: *(a + 5) and 5[a] will evaluate to: *(5 + a) a is a pointer to the first element of the array. a[5] is the value that’s 5 elements further from a, which is the same … Read more
It’s very unfortunate that you see dynamic allocation so often. That just shows how many bad C++ programmers there are. In a sense, you have two questions bundled up into one. The first is when should we use dynamic allocation (using new)? The second is when should we use pointers? The important take-home message is … Read more
static_cast static_cast is used for cases where you basically want to reverse an implicit conversion, with a few restrictions and additions. static_cast performs no runtime checks. This should be used if you know that you refer to an object of a specific type, and thus a check would be unnecessary. Example: void func(void *data) { … Read more
UPDATE This answer is rather old, and so describes what was ‘good’ at the time, which was smart pointers provided by the Boost library. Since C++11, the standard library has provided sufficient smart pointers types, and so you should favour the use of std::unique_ptr, std::shared_ptr and std::weak_ptr. There was also std::auto_ptr. It was very much … 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
A pointer can be re-assigned: int x = 5; int y = 6; int *p; p = &x; p = &y; *p = 10; assert(x == 5); assert(y == 10); A reference cannot be re-bound, and must be bound at initialization: int x = 5; int y = 6; int &q; // error int &r … Read more