Lesson 19. The Maybe type: dealing with missing values
After reading lesson 19, you’ll be able to
- Understand the Maybe type
- Use the Maybe type to handle missing values
- Design programs with Maybe types
Just as type classes can often be much more abstract than interfaces in OOP, parameterized types play a much larger role than generics do in most languages. This lesson introduces an important parameterized type: Maybe. Unlike List or Map, which represent containers for values, Maybe is the first of many types you’ll see that represents a context for a value. Maybe types represent values that might be missing. In most languages, a missing value is represented by the null value. By using a context representing a value that might be missing, ...
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