Explicit Cast

The compiler performs implicit casts during operations. However, C++ allows us to apply explicit casts as well.

There are 4 different named cast operators:

• dynamic_cast
• static_cast
• const_cast
• reinterpret_cast

The functionality of each operator will be discussed shortly.

Syntax

Explicit cast operators require the type that we want to cast our data in. They can be used in the following way:

double myDouble{5.5};
int i = static_cast<int>(myDouble);

C-casts

C-Casts are primitive cast operators that convert data from one type to another. They use the following format:

(type) value_or_expression

Here’s an example:

double myDouble{5.5};
int i = (int)myDouble;

We should avoid using C-casts since they present a number of problems.

What is bad about the C-cast? We don’t see which cast is actually used. If we perform a C-cast, a combination of casts will be applied, if necessary. Roughly speaking, a C-cast starts with a static_cast, continues with a const_cast, and finally performs a reinterpret_cast.

Let’s see what happens if we screw up the type system: