Chapter 6. Dealing with optional data
This chapter covers
- The null reference, or “the billion-dollar mistake”
- Alternatives to null references
- Developing an Option data type for optional data
- Applying functions to optional values
- Composing optional values
- Option use cases
Representing optional data in computer programs has always been a problem. The concept of optional data is very simple in everyday life. Representing the absence of something when this something is contained in a container is easy—whatever it is, it can be represented by an empty container. An absence of apples can be represented by an empty apple basket. The absence of gasoline in a car can be visualized as an empty gas tank.
Representing the absence of data in computer ...