Data Types

The D programming language defines 3 classes of data types:

1. Basic data types: such as int, float, long etc. that are similar to the ones provided by C;
2. Derived data types: pointer, array, associative array, delegate, function;
3. User defined types: class, struct, union, enum;

We will not insist on basic data types and pointers, as those are the same (or slightly modified versions) as the ones in C\C++. We will focus on arrays, associative arrays, classes, structs and unions. Delegates, functions and enums will be treated in a future lab.

Note that in D all types have a default value. This means that there are no uninitialized variables.

    int a; // equivalent to int a = 0;
    int *p; // equivalent to int *p = null;
    // The same goes for structs and classes: their fields are recursively initialised.