Soar with Haskell

2

Algebraic Datatypes

While functions are, of course, central in functional programming, they have to have values to process. Haskell classifies values by means of types and provides a number of built-in types such as Integer and Bool. Yet, these built-in types are rather limited and rather generic. For this reason, Haskell provides a facility for defining user-defined datatypes, called algebraic datatypes.

This chapter explains how algebraic datatypes work. We first study two simple forms of algebraic datatypes (enumerations and records) that have well-known counterparts in other programming languages. Then, we merge the two features into the full-blown form of algebraic datatypes. We learn about the different elements of an algebraic datatype ...