Chapter 15 Stability

Table of Contents

15.1 Stability Levels
15.2 Dependency Classes
15.3 Interface Attributes
15.4 Stability Computations and Reports
15.5 Stability Enforcement

Developers are provided with early access to new technologies as well as observability tools that allow users to peer into the internal implementation details of user and kernel software. Unfortunately, new technologies and internal implementation details are both prone to changes as interfaces and implementations evolve and mature when software is upgraded or patched. Application and interface stability levels are documented using a set of labels to help set user expectations for what kinds of changes might occur in different kinds of future releases. No one stability attribute appropriately describes the arbitrary set of entities and services that can be accessed from a D program. DTrace and the D compiler therefore include features to dynamically compute and describe the stability levels of D programs you create. This chapter discusses the DTrace features for determining program stability to help you design stable D programs. You can use the DTrace stability features to inform you of the stability attributes of your D programs, or to produce compile-time errors when your program has undesirable interface dependencies.