conversations.from: human
conversations.value: What could be a title for a story about Ecole, Fatih, Swift with the genre: Computers & Technology, Programming Languages?
conversations.from: assistant
conversations.value: A title for this story could be 'Swift 3 Functional Programming'
conversations.from: human
conversations.value: Give me the first five paragraphs for this story.. End with the sentence ' For instance, the following example forcefully unwraps the `optionalString` variable:'.
conversations.from: assistant
conversations.value: Swift 3 Functional Programming
  Type aliases define an alternative name for an existing type. We define type aliases with the `typealias` keyword. Type aliases are useful when we want to refer to an existing type by a name that is contextually more appropriate, such as when working with data of a specific size from an external source. For instance, in the following example, we provide an alias for an unsigned 32-bit integer that can be used later in our code:
  Swift makes it possible to define variables as mutable and immutable. The `let` keyword is used for immutable declarations and the `var` keyword is used for mutable declarations. Any variable that is declared with the `let` keyword will not be open to change. In the following examples, we define `aMutableString` with the `var` keyword so that we will be able to alter it later on; in contrast, we will not be able to alter `aConstString` that is defined with the `let` keyword:
  Swift provides tuples so that they can be used to group multiple values into a single compound value. Let's consider the following example:
  Swift provides optionals so they can be used in situations where a value may be absent. An optional will have some or none values. The `?` symbol is used to define a variable as optional. Let's consider the following example:
  The `!` symbol can be used to forcefully unwrap the value from an optional. For instance, the following example forcefully unwraps the `optionalString` variable:
conversations.from: human
conversations.value: Give me two more paragraphs.
conversations.from: assistant
conversations.value: We can use `reduce` to partition an array with a specific criterion. For instance, in the following example, we partition `numbersToPartition` `Array` into two partitions, keeping all even numbers in the left partition:
  In this chapter, we started with the category theory concepts such as Functor, Applicative Functor, and Monad and explored higher-order functions such as `map`, `filter`, `flatMap`, `flatten`, and `reduce`. Also, we developed `map`, `filter`, `flatMap`, and `flatten` functions in terms of the `reduce` function.
conversations.from: human
conversations.value: Add another sentence about Swift-provided, examined, Swift-provided, implemented.
conversations.from: assistant
conversations.value: We can use `reduce` to partition an array with a specific criterion. For instance, in the following example, we partition `numbersToPartition` `Array` into two partitions, keeping all even numbers in the left partition:
  In this chapter, we started with the category theory concepts such as Functor, Applicative Functor, and Monad and explored higher-order functions such as `map`, `filter`, `flatMap`, `flatten`, and `reduce`. Then, we examined Swift-provided versions of higher-order functions and implemented a simple version ourselves. Also, we developed `map`, `filter`, `flatMap`, and `flatten` functions in terms of the `reduce` function.
conversations.from: human
conversations.value: Give me the last three paragraphs.
conversations.from: assistant
conversations.value: In our `viewDidLoad` method, we look for the selected item in `MasterViewController` before navigating to `DetailsViewController`. We will also set the `UITextField` and `UISwitch` initial values. We will subscribe to changes in the UI, use lenses to update the `Todo` item, and change the state via `UpdateTodoAction`. Any item change will set synced as false. Since this property is observed in `MasterViewController`, any changes to the UI in `DetailsViewController` will be synced with the backend without any extra effort.
  In this chapter, we developed a backend with Swift Vapor library that handles the `Todo` items `POST`, `GET`, and `DELETE`. Then, we developed a frontend iOS application that leverages functional programming, reactive programming, and state management techniques declaratively. We started by developing our `Todo` model in a functional style, and then we developed `Store` and its extensions to handle `State` storage and `Action` to handle `State` changes. We defined and used `Lens` to modify our properties and a `WebServiceManager` with reflection techniques to request for backend resources.
  In this case study, we were able to use value types such as `struct` and `enum` and avoid classes. In fact, the only four classes in this case study are related to the iOS SDK (`UIViewController`, `UITableViewController`, `UITableViewCell`, and `UIView` subclasses). We were able to centralize all state mutations into `Store` only using `Action` to change the `State` in the `Store`. Although we did not develop any unit test cases, it is recommended that you explore functional programming unit testing libraries such as **Quick** to ensure the quality of code.
conversations.from: human
conversations.value: Delete the last sentence.
conversations.from: assistant
conversations.value: In our `viewDidLoad` method, we look for the selected item in `MasterViewController` before navigating to `DetailsViewController`. We will also set the `UITextField` and `UISwitch` initial values. We will subscribe to changes in the UI, use lenses to update the `Todo` item, and change the state via `UpdateTodoAction`. Any item change will set synced as false. Since this property is observed in `MasterViewController`, any changes to the UI in `DetailsViewController` will be synced with the backend without any extra effort.
  In this chapter, we developed a backend with Swift Vapor library that handles the `Todo` items `POST`, `GET`, and `DELETE`. Then, we developed a frontend iOS application that leverages functional programming, reactive programming, and state management techniques declaratively. We started by developing our `Todo` model in a functional style, and then we developed `Store` and its extensions to handle `State` storage and `Action` to handle `State` changes. We defined and used `Lens` to modify our properties and a `WebServiceManager` with reflection techniques to request for backend resources.
  In this case study, we were able to use value types such as `struct` and `enum` and avoid classes. In fact, the only four classes in this case study are related to the iOS SDK (`UIViewController`, `UITableViewController`, `UITableViewCell`, and `UIView` subclasses). We were able to centralize all state mutations into `Store` only using `Action` to change the `State` in the `Store`.