iOS Programming Cookbook
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Getting ready

In Swift, syntax is pretty easy, and that's why it is awesome. To extend any type, just type the following:

extension TypeToBeExtended{ 
} 

Inside the curly braces, you can add your extensions to the type to be extended. In extension, you can do the following:

  • Adding instance- or class-computed properties
  • Adding instance or class methods
  • Adding new initializers
  • Defining subscripts
  • Adding nested types
  • Conforming to protocols

Once you create an extension to any type, the new functionality will be available for all instances in the whole project.