SwiftRebound is a library for binding Swift programs together.

SwiftRebound

Basic usage

Create a bound variable

let binding = Binding.create(1);

Observe it for changes

binding.observe { newValue in print(newValue); }.forever();
binding.value = 3; /// prints '3'

Derive a computed binding

let computed = Binding.computed { binding.value + 1 };
computed.observe { newValue in print(newValue); }.forever();
binding.value = 5; /// prints '6' (well, and '5' with the above binding ;-)

Manage binding lifetimes

let lifetime = binding.observe { newValue in print(newValue); };
binding.value = 1; /// prints
lifetime.done();
binding.value = 2; /// observer no longer runs

let lifetime = binding.observe { newValue in print(newValue); };
lifetime.forever();
binding.value = 1; /// prints
binding.value = 2; /// observe lasts as long as binding

var someView: NSView = view;
let lifetime = binding.observe { newValue in print(newValue); };
lifetime.liveAsLongAs(someView); /// binding will go away when the view goes away

Do Key-Value observation

class ObservableObject : NSObject {
    dynamic var foo = 0;
}

let kvo = ObservableObject();
let bound = kvo.bindKeyPath("foo");
let value = bound.value as! Int;    /// == 0

let lifetime = bound.observe { newValue in print(newValue); }
kvo.foo = 1;        /// Prints '1'
lifetime.done();    /// Must stop observing KVO bindings to allow the target object to be released