A compilation unit.

There are three kinds of compilation unit:

• Regular compilation units contain toplevel type, value, or function definitions.
• Module descriptor compilation units contain a module descriptor.
• Package descriptor compilation units contain a package descriptor.

(Because it is the most commonly used, and also what most people associate with a “compilation unit”, the first kind is simply called CompilationUnit and this abstract class is called AnyCompilationUnit, rather than calling this CompilationUnit and using RegularCompilationUnit or CodeCompilationUnit for regular compilation units.)

Every compilation unit starts with a (possibly empty) list of imports.

Examples (separated by blank lines):

module tmp "1.0.0" {}

package tmp;

void run() {
    print("Hello, World!");
}