0001    //
0002    //  Variable.swift
0003    //  Rx
0004    //
0005    //  Created by Krunoslav Zaher on 3/28/15.
0006    //  Copyright © 2015 Krunoslav Zaher. All rights reserved.
0007    //
0008    
0009    import Foundation
0010    
0011    /**
0012    Variable is a wrapper for `BehaviorSubject`.
0013    
0014    Unlike `BehaviorSubject` it can't terminate with error, and when variable is deallocated
0015     it will complete it's observable sequence (`asObservable`).
0016    */
0017    public class Variable<Element
Variable.swift:19
    public typealias E = Element
Variable.swift:21
    private let _subject: BehaviorSubject<Element>
Variable.swift:54
    public init(_ value: Element) {> {
0018    
0019        public typealias E
Variable.swift:26
    private var _value: E
Variable.swift:35
    public var value: E {
Variable.swift:62
    public func asObservable() -> Observable<E> { = Element
0020        
0021        private let _subject
Variable.swift:45
            _subject.on(.Next(newValue))
Variable.swift:56
        _subject = BehaviorSubject(value: value)
Variable.swift:63
        return _subject
Variable.swift:67
        _subject.on(.Completed): BehaviorSubject<Element>
0022        
0023        private var _lock
Variable.swift:37
            _lock.lock(); defer { _lock.unlock() }
Variable.swift:37
            _lock.lock(); defer { _lock.unlock() }
Variable.swift:41
            _lock.lock()
Variable.swift:43
            _lock.unlock() = SpinLock()
0024     
0025        // state
0026        private var _value
Variable.swift:38
            return _value
Variable.swift:42
            _value = newValue
Variable.swift:55
        _value = value: E
0027        
0028        /**
0029        Gets or sets current value of variable.
0030        
0031        If case new value is set, all observers are notified of that change.
0032        
0033        Even is case equal value is set, observers will still be notified.
0034        */
0035        public var value: E {
0036            get {
0037                _lock.lock(); defer { _lock.unlock() }
0038                return _value
0039            }
0040            set(newValue) {
0041                _lock.lock()
0042                _value = newValue
0043                _lock.unlock()
0044    
0045                _subject.on(.Next(newValue))
0046            }
0047        }
0048        
0049        /**
0050        Initializes variable with initial value.
0051        
0052        - parameter value: Initial variable value.
0053        */
0054        public init(_ value: Element) {
0055            _value = value
0056            _subject = BehaviorSubject(value: value)
0057        }
0058        
0059        /**
0060        - returns: Canonical interface for push style sequence
0061        */
0062        public func asObservable() -> Observable<E> {
0063            return _subject
0064        }
0065    
0066        deinit {
0067            _subject.on(.Completed)
0068        }
0069    }