What is Generics in Swift


What is Generics?

  • Generic enables you to write flexible, reusable functions and types that can work with any type, subject to requirements that you define.
  • Generics are used to avoid duplication and to provide abstraction.
  • Generics are type safe, meaning if you pass a string as a generic and try to use as a integer the compiler will complain and you will not be able to compile your code. (This happens because Swift is using Static typing, and is able to give you a compiler error)
  • If you use AnyObject the compiler has no idea if the object can be treated as a String or as an Integer. It will allow you to do whatever you want with it.
  • 'Arrays' and 'Dictionary' types belong to generic collections. With the help of arrays and dictionaries the arrays are defined to hold 'Int' values and 'String' values or any other types.
  • There is just one rule if you want to make your function generic. All you need to do is put <anything> right next to a function name. 

    Example:

       
func doanything<T>(value: T) {

 print(value)
}


doanything(value: 012)     // Int

doanything(value: "Pawan")   // String

doanything(value: 112.12)  // Double

doanything(value: true)    // Bool



Thanks for reading, Happy Coding 👨‍💻

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