Utility

Assign

This function is used to copy the values of all enumerable own properties from one or more source struct to a target struct. If the argument is a reference type the same refence is returned.

public func assign<T>(_ value: T, changes: (inout T) -> Void) -> T

Partial

Constructs a type with all properties of T set to optional. This utility will return a type that represents all subsets of a given type.

struct Todo { var title: String; var description: String } 
var partial = Partial { .success(Todo(
 title: $0.get(\Todo.title, default: "Untitled"),   
 description: $0.get(\Todo.description, default: "No description"))) 
} 
partial.title = "A Title" 
partial.description = "A Description" 
var todo = try! partial.build().get() 
partial.description = "Another Descrition" 
todo = partial.merge(&todo) 

ReadOnly

Constructs a type with all properties of T set to readonly, meaning the properties of the constructed type cannot be reassigned. Note: A read-only object propagetes observable changes from its wrapped object.

struct Todo { var title: String; var description: String }
let todo = Todo(title: "A Title", description: "A Description")
let readOnlyTodo = ReadOnly(todo)
readOnlyTodo.title // "A title"

Proxy

Creates an observable Proxy for the object passed as argument.

struct Todo { var title: String; var description: String }
let todo = Todo(title: "A Title", description: "A Description")
let proxy = Proxy(todo)
proxy.propertyDidChange.sink {
  if $0.match(keyPath: \.title) {
    ...
  }
}
proxy.title = "New Title"