Pattern Matching on Literals

Explore how to use literal values as patterns in Haskell function definitions. Understand the matching rules for literals versus pattern variables, including the use of wildcards, and see examples with numeric and Boolean types. This lesson helps you write functions that handle special cases elegantly using literal pattern matching.

We'll cover the following...

- Pattern matching on literals
- - Wildcard patterns
  - Literal patterns for other types

Pattern matching on literals

Instead of using pattern variables, we can also write function equations using literal values as patterns. Here is an example:

isZero :: Int -> Bool
isZero 0 = True
isZero n = False

This function has two defining equations. The first one uses the numeric literal 0 as the pattern. We can read it as "if the argument to isZero is 0 ...

1.Introduction

2.First Steps with Haskell

3.Techniques for Writing Functions

4.Working with Lists

5.Creating Data Types

6.Input and Output

7.Conclusion

8.Appendix

Pattern Matching on Literals

Pattern matching on literals