Type-safe enumerations

Often there is the necessity to define functionality based on a set of values. If you have experience in C, you may have seen typedef enum { WHITE, BLACK, YELLOW } color_t; before. In PHP, one could write something like define('WHITE', 0); and define('BLACK', 1); which is pretty much what the C version does. The problem with these approaches are that they are not type-safe, and functionality needs to be attached by using switch or if-else cascades.

Here's some more information on enums in the XP framework:

From our blog

• Enum usecases: Replace switch/case blocks
• Enum usecases: Profiling
• EASC and enum types

History

Enums were first introduced in July 2007 within RFC 0132.

Table of contents

• Further reading