Custom subscripts were added to Objective-C in 2012. At that time, Chris Lattner was already two years into developing Swift, and, like other good features, subscripts were added to the Swift language. I have not used custom subscripts in many other languages, however, I do find myself using subscripts extensively when I am developing in Swift. The syntax for using subscripts in Swift seems like a natural part of the language, possibly because they were part of the language when it was released and not added in later. Once you start using subscripts in Swift, you may find them indispensable.
In this chapter, we will cover the following topics:
- What are custom subscripts?
- Adding custom subscripts to classes, structures, or enumerations
- Creating read/write and read-only subscripts
- Using external names without custom subscripts
- Using multidimensional subscripts...