Make diction of docs and api naming more corresponding with official api.

Schedule.xcodeproj/project.pbxproj

@@ -24,7 +24,6 @@
 		OBJ_49 /* Atomic.swift in Sources */ = {isa = PBXBuildFile; fileRef = OBJ_9 /* Atomic.swift */; };
 		OBJ_50 /* Bag.swift in Sources */ = {isa = PBXBuildFile; fileRef = OBJ_10 /* Bag.swift */; };
 		OBJ_51 /* DeinitObserver.swift in Sources */ = {isa = PBXBuildFile; fileRef = OBJ_11 /* DeinitObserver.swift */; };
-		OBJ_52 /* Deprecated.swift in Sources */ = {isa = PBXBuildFile; fileRef = OBJ_12 /* Deprecated.swift */; };
 		OBJ_53 /* Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = OBJ_13 /* Extensions.swift */; };
 		OBJ_54 /* Interval.swift in Sources */ = {isa = PBXBuildFile; fileRef = OBJ_14 /* Interval.swift */; };
 		OBJ_55 /* Monthday.swift in Sources */ = {isa = PBXBuildFile; fileRef = OBJ_15 /* Monthday.swift */; };
@@ -70,7 +69,6 @@
 /* Begin PBXFileReference section */
 		OBJ_10 /* Bag.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Bag.swift; sourceTree = "<group>"; };
 		OBJ_11 /* DeinitObserver.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DeinitObserver.swift; sourceTree = "<group>"; };
-		OBJ_12 /* Deprecated.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Deprecated.swift; sourceTree = "<group>"; };
 		OBJ_13 /* Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Extensions.swift; sourceTree = "<group>"; };
 		OBJ_14 /* Interval.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Interval.swift; sourceTree = "<group>"; };
 		OBJ_15 /* Monthday.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Monthday.swift; sourceTree = "<group>"; };
@@ -157,7 +155,7 @@
 			name = Products;
 			sourceTree = BUILT_PRODUCTS_DIR;
 		};
-		OBJ_5 /*  */ = {
+		OBJ_5 = {
 			isa = PBXGroup;
 			children = (
 				OBJ_6 /* Package.swift */,
@@ -170,7 +168,6 @@
 				OBJ_42 /* README.md */,
 				OBJ_43 /* README.zh_cn.md */,
 			);
-			name = "";
 			sourceTree = "<group>";
 		};
 		OBJ_7 /* Sources */ = {
@@ -187,7 +184,6 @@
 				OBJ_9 /* Atomic.swift */,
 				OBJ_10 /* Bag.swift */,
 				OBJ_11 /* DeinitObserver.swift */,
-				OBJ_12 /* Deprecated.swift */,
 				OBJ_13 /* Extensions.swift */,
 				OBJ_14 /* Interval.swift */,
 				OBJ_15 /* Monthday.swift */,
@@ -271,7 +267,7 @@
 				English,
 				en,
 			);
-			mainGroup = OBJ_5 /*  */;
+			mainGroup = OBJ_5;
 			productRefGroup = OBJ_36 /* Products */;
 			projectDirPath = "";
 			projectRoot = "";
@@ -292,7 +288,6 @@
 				OBJ_49 /* Atomic.swift in Sources */,
 				OBJ_50 /* Bag.swift in Sources */,
 				OBJ_51 /* DeinitObserver.swift in Sources */,
-				OBJ_52 /* Deprecated.swift in Sources */,
 				OBJ_53 /* Extensions.swift in Sources */,
 				OBJ_54 /* Interval.swift in Sources */,
 				OBJ_55 /* Monthday.swift in Sources */,

Sources/Schedule/Atomic.swift

@@ -1,31 +1,38 @@
 import Foundation
 
-/// Represents a box that can read and write the underlying value atomically.
+/// An atomic box that can read and write the underlying value atomically.
 final class Atomic<T> {
 
-    private var v: T
+    private var val: T
     private let lock = NSLock()
 
-    /// Init with the underlying value.
+    /// Create an atomic box with the given initial value.
-    init(_ value: T) {
-        self.v = value
-    }
-
-    /// Creates a snapshot of the value nonatomically.
     @inline(__always)
-    func snapshot() -> T {
+    init(_ value: T) {
-        return v
+        self.val = value
     }
 
-    /// Reads the value atomically.
+    /// Reads the current value atomically.
     @inline(__always)
     func read<U>(_ body: (T) -> U) -> U {
-        return lock.withLock { body(v) }
+        return lock.withLock { body(val) }
     }
     
-    /// Writes the value atomically.
+    /// Reads the current value atomically.
+    @inline(__always)
+    func readVoid(_ body: (T) -> Void) {
+        lock.withLockVoid { body(val) }
+    }
+
+    /// Writes the current value atomically.
     @inline(__always)
     func write<U>(_ body: (inout T) -> U) -> U {
-        return lock.withLock { body(&v) }
+        return lock.withLock { body(&val) }
+    }
+    
+    /// Writes the current value atomically.
+    @inline(__always)
+    func writeVoid(_ body: (inout T) -> Void) {
+        lock.withLockVoid { body(&val) }
     }
 }

Sources/Schedule/Bag.swift

@@ -1,6 +1,6 @@
 import Foundation
 
-/// A unique key used to operate the corresponding element from a bag.
+/// A unique key for removing an element from a bag.
 struct BagKey: Equatable {
 
     fileprivate let i: UInt64
@@ -15,7 +15,7 @@ struct BagKey: Equatable {
     }
 }
 
-/// A generator used to generate a sequence of unique `BagKey`.
+/// A generator that can generate a sequence of unique `BagKey`.
 ///
 ///     let k1 = gen.next()
 ///     let k2 = gen.next()
@@ -26,8 +26,8 @@ struct BagKeyGenerator: Sequence, IteratorProtocol {
 
     private var k = BagKey(underlying: 0)
 
-    /// Advances to the next element and returns it, or nil if no next element exists.
+    /// Advances to the next key and returns it, or nil if no next key exists.
-    mutating func next() -> Element? {
+    mutating func next() -> BagKey? {
         if k.i == UInt64.max {
             return nil
         }
@@ -36,7 +36,7 @@ struct BagKeyGenerator: Sequence, IteratorProtocol {
     }
 }
 
-/// A data structure used to store a sequence of elements.
+/// An ordered sequence.
 ///
 ///     let k1 = bag.append(e1)
 ///     let k2 = bag.append(e2)
@@ -46,48 +46,48 @@ struct BagKeyGenerator: Sequence, IteratorProtocol {
 ///         // -> e2
 ///     }
 ///
-///     bag.delete(k1)
+///     bag.removeValue(for: k1)
 struct Bag<Element> {
 
-    private typealias Entry = (key: BagKey, element: Element)
+    private typealias Entry = (key: BagKey, val: Element)
 
-    private var keys = BagKeyGenerator()
+    private var keyGen = BagKeyGenerator()
     private var entries: [Entry] = []
 
-    /// Pushes the given element on to the end of this container.
+    /// Appends a new element at the end of this bag.
     @discardableResult
     mutating func append(_ new: Element) -> BagKey {
-        let key = keys.next()!
+        let key = keyGen.next()!
 
-        let entry = (key: key, element: new)
+        let entry = (key: key, val: new)
         entries.append(entry)
 
         return key
     }
 
-    /// Returns the element for key if key is in this container.
+    /// Returns the element associated with a given key.
-    func get(_ key: BagKey) -> Element? {
+    func value(for key: BagKey) -> Element? {
         if let entry = entries.first(where: { $0.key == key }) {
-            return entry.element
+            return entry.val
         }
         return nil
     }
 
-    /// Deletes the element with the given key and returns this element.
+    /// Removes the given key and its associated element from this bag.
     @discardableResult
-    mutating func delete(_ key: BagKey) -> Element? {
+    mutating func removeValue(for key: BagKey) -> Element? {
         if let i = entries.firstIndex(where: { $0.key == key }) {
-            return entries.remove(at: i).element
+            return entries.remove(at: i).val
         }
         return nil
     }
 
-    /// Removes all elements from this containers.
+    /// Removes all elements from this bag.
-    mutating func clear() {
+    mutating func removeAll() {
         entries.removeAll()
     }
 
-    /// The number of elements in this containers.
+    /// The number of elements in this bag.
     var count: Int {
         return entries.count
     }
@@ -95,11 +95,12 @@ struct Bag<Element> {
 
 extension Bag: Sequence {
 
-    /// Returns an iterator over the elements of this containers.
+    /// Returns an iterator over the elements of this bag.
+    @inline(__always)
     func makeIterator() -> AnyIterator<Element> {
         var iterator = entries.makeIterator()
         return AnyIterator<Element> {
-            return iterator.next()?.element
+            return iterator.next()?.val
         }
     }
 }

Sources/Schedule/DeinitObserver.swift

@@ -2,9 +2,7 @@ import Foundation
 
 #if canImport(ObjectiveC)
 
-private var DEINIT_OBSERVER_KEY: Void = ()
+/// An observer that receives deinit event of the object.
-
-/// Used to observe object deinit.
 ///
 ///     let observer = DeinitObserver.observe(target) {
 ///         print("\(target) deinit")
@@ -13,38 +11,40 @@ private var DEINIT_OBSERVER_KEY: Void = ()
 ///     observer.cancel()
 class DeinitObserver {
     
+    private var associateKey: Void = ()
+    
     private(set) weak var observed: AnyObject?
 
-    private var action: (() -> Void)?
+    private var block: (() -> Void)?
 
-    private init(_ action: @escaping () -> Void) {
+    private init(_ block: @escaping () -> Void) {
-        self.action = action
+        self.block = block
     }
 
-    /// Add observer.
+    /// Observe deinit event of the object.
     @discardableResult
     static func observe(
         _ object: AnyObject,
-        onDeinit action: @escaping () -> Void
+        using block: @escaping () -> Void
     ) -> DeinitObserver {
-        let observer = DeinitObserver(action)
+        let observer = DeinitObserver(block)
         observer.observed = object
 
-        objc_setAssociatedObject(object, &DEINIT_OBSERVER_KEY, observer, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
+        objc_setAssociatedObject(object, &observer.associateKey, observer, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
 
         return observer
     }
 
-    /// Remove observer.
+    /// Cancel observing.
     func cancel() {
-        action = nil
+        block = nil
         if let o = observed {
-            objc_setAssociatedObject(o, &DEINIT_OBSERVER_KEY, nil, .OBJC_ASSOCIATION_ASSIGN)
+            objc_setAssociatedObject(o, &associateKey, nil, .OBJC_ASSOCIATION_ASSIGN)
         }
     }
 
     deinit {
-        action?()
+        block?()
     }
 }
 

Sources/Schedule/Deprecated.swift

@@ -1,59 +0,0 @@
-//
-//  Deprecated.swift
-//  Schedule
-//
-//  Created by Quentin Jin on 2019/3/4.
-//  Copyright © 2019 Schedule. All rights reserved.
-//
-
-import Foundation
-
-extension Monthday {
-
-    /// A Boolean value indicating whether today is the monthday.
-    @available(*, deprecated, message: "Use date.is(_:Monthday)")
-    public var isToday: Bool {
-        let components = toDateComponents()
-
-        let m = Calendar.gregorian.component(.month, from: Date())
-        let d = Calendar.gregorian.component(.day, from: Date())
-
-        return m == components.month && d == components.day
-    }
-}
-
-extension Weekday {
-
-    /// A Boolean value indicating whether today is the weekday.
-    @available(*, deprecated, message: "Use date.is(_:Weekday)")
-    public var isToday: Bool {
-        return Calendar.gregorian.component(.weekday, from: Date()) == rawValue
-    }
-}
-
-extension Time {
-
-    /// The interval between this time and zero o'clock.
-    @available(*, deprecated, renamed: "intervalSinceStartOfDay")
-    public var intervalSinceZeroClock: Interval {
-        return hour.hours + minute.minutes + second.seconds + nanosecond.nanoseconds
-    }
-}
-
-extension Plan {
-
-    /// Creates a plan from an interval sequence.
-    /// The task will be executed after each interval in the sequence.
-    @available(*, deprecated, message: "Use Plan.of")
-    public static func from<S>(_ sequence: S) -> Plan where S: Sequence, S.Element == Interval {
-        return Plan.of(sequence)
-    }
-
-    /// Creates a plan from a date sequence.
-    /// The task will be executed at each date in the sequence.
-    /// - Note: Returns `Plan.never` if given no parameters.
-    @available(*, deprecated, message: "Use Plan.of")
-    public static func from<S>(_ sequence: S) -> Plan where S: Sequence, S.Element == Date {
-        return Plan.make(sequence.makeIterator)
-    }
-}

Sources/Schedule/Extensions.swift

@@ -2,6 +2,7 @@ import Foundation
 
 extension Double {
 
+    /// Returns a value of this number clamped to `Int.min...Int.max`.
     func clampedToInt() -> Int {
         if self >= Double(Int.max) { return Int.max }
         if self <= Double(Int.min) { return Int.min }
@@ -11,13 +12,11 @@ extension Double {
 
 extension Int {
 
+    /// Returns the sum of the two given values, in case of any overflow,
+    /// the result will be clamped to int.
     func clampedAdding(_ other: Int) -> Int {
         return (Double(self) + Double(other)).clampedToInt()
     }
-
-    func clampedSubtracting(_ other: Int) -> Int {
-        return clampedAdding(-other)
-    }
 }
 
 extension Calendar {
@@ -47,9 +46,9 @@ extension NSLocking {
         return try body()
     }
 
-    /// Executes a closure returning a value while acquiring the lock.
+    /// Executes a closure while acquiring the lock.
     @inline(__always)
-    func withLock(_ body: () throws -> Void) rethrows {
+    func withLockVoid(_ body: () throws -> Void) rethrows {
         lock(); defer { unlock() }
         try body()
     }

Sources/Schedule/Interval.swift

@@ -1,6 +1,6 @@
 import Foundation
 
-/// `Interval` represents a length of time.
+/// Type used to represent a time-based amount of time, such as '34.5 seconds'.
 public struct Interval {
 
     ///  The length of this interval in nanoseconds.
@@ -13,36 +13,26 @@ public struct Interval {
 }
 
 // MARK: - Describing
+
 extension Interval {
 
-    /// A boolean value indicating whether this interval is less than zero.
+    /// A Boolean value indicating whether this interval is less than zero.
     ///
-    /// An interval can be negative:
     ///
-    /// - The interval from 6:00 to 7:00 is `1.hour`,
+    /// An Interval represents a directed distance between two points
-    ///   but the interval from 7:00 to 6:00 is `-1.hour`.
+    /// on the time-line and can therefore be positive, zero or negative.
-    ///   In this case, `-1.hour` means **one hour ago**.
-    ///
-    /// - The interval comparing `3.hour` to `1.hour` is `2.hour`,
-    ///   but the interval comparing `1.hour` to `3.hour` is `-2.hour`.
-    ///   In this case, `-2.hour` means **two hours shorter**
     public var isNegative: Bool {
         return nanoseconds < 0
     }
 
-    /// See `isNegative`.
+    /// A copy of this duration with a positive length.
-    public var isPositive: Bool {
+    public var abs: Interval {
-        return nanoseconds > 0
+        return Interval(nanoseconds: Swift.abs(nanoseconds))
     }
 
-    /// The absolute value of the length of this interval in nanoseconds.
+    /// A copy of this interval with the length negated.
-    public var magnitude: Double {
+    public var negated: Interval {
-        return nanoseconds.magnitude
+        return Interval(nanoseconds: -nanoseconds)
-    }
-
-    /// The additive inverse of this interval.
-    public var opposite: Interval {
-        return (-nanoseconds).nanoseconds
     }
 }
 
@@ -75,18 +65,22 @@ extension Interval: CustomDebugStringConvertible {
 }
 
 // MARK: - Comparing
+
 extension Interval: Comparable {
 
-    /// Compares two intervals.
+    /// Compares two intervals and returns a comparison result value
+    /// that indicates the sort order of two intervals.
     ///
-    /// The comparison is magnitude independent, a positive interval is
+    /// A positive interval is always ordered ascending to a negative interval.
-    /// always ordered ascending to a negative interval.
     public func compare(_ other: Interval) -> ComparisonResult {
-        let now = Date()
+        let d = nanoseconds - other.nanoseconds
-        return now.adding(self).compare(now.adding(other))
+        
+        if d < 0 { return .orderedAscending }
+        if d > 0 { return .orderedDescending }
+        return .orderedSame
     }
 
-    /// Returns a boolean value indicating whether the first interval is
+    /// Returns a Boolean value indicating whether the first interval is
     /// less than the second interval.
     ///
     /// A negative interval is always less than a positive interval.
@@ -94,43 +88,23 @@ extension Interval: Comparable {
         return lhs.compare(rhs) == .orderedAscending
     }
 
-    /// Returns a boolean value indicating whether this interval is longer
+    /// Returns a Boolean value indicating whether this interval is longer
-    /// than the given value.
+    /// than the given interval.
     public func isLonger(than other: Interval) -> Bool {
-        return magnitude > other.magnitude
+        return abs > other.abs
     }
 
-    /// Returns a boolean value indicating whether this interval is shorter
+    /// Returns a Boolean value indicating whether this interval is shorter
-    /// than the given value.
+    /// than the given interval.
     public func isShorter(than other: Interval) -> Bool {
-        return magnitude < other.magnitude
+        return abs < other.abs
-    }
-
-    /// Returns the longest interval of the given values.
-    public static func longest(_ intervals: Interval...) -> Interval {
-        return longest(intervals)!
-    }
-
-    /// Returns the longest interval of the given values.
-    public static func longest(_ intervals: [Interval]) -> Interval? {
-        guard !intervals.isEmpty else { return nil }
-        return intervals.sorted(by: { $0.magnitude > $1.magnitude })[0]
-    }
-
-    /// Returns the shortest interval of the given values.
-    public static func shortest(_ intervals: Interval...) -> Interval {
-        return shortest(intervals)!
-    }
-
-    /// Returns the shortest interval of the given values.
-    public static func shortest(_ intervals: [Interval]) -> Interval? {
-        guard !intervals.isEmpty else { return nil }
-        return intervals.sorted(by: { $0.magnitude < $1.magnitude })[0]
     }
 }
 
 // MARK: - Adding & Subtracting
+
 extension Interval {
+    
     /// Returns a new interval by multipling this interval by the given number.
     ///
     ///     1.hour * 2 == 2.hours
@@ -144,13 +118,6 @@ extension Interval {
     public func adding(_ other: Interval) -> Interval {
         return Interval(nanoseconds: nanoseconds + other.nanoseconds)
     }
-
-    /// Returns a new interval by subtracting the given interval from this interval.
-    ///
-    ///     2.hours - 1.hour == 1.hour
-    public func subtracting(_ other: Interval) -> Interval {
-        return Interval(nanoseconds: nanoseconds - other.nanoseconds)
-    }
 }
 
 // MARK: - Operators
@@ -174,21 +141,22 @@ extension Interval {
     ///
     ///     2.hours - 1.hour == 1.hour
     public static func - (lhs: Interval, rhs: Interval) -> Interval {
-        return lhs.subtracting(rhs)
+        return lhs.adding(rhs.negated)
     }
 
-    /// Adds two intervals and stores the result in the first interval.
+    /// Adds two intervals and stores the result in the left interval.
     public static func += (lhs: inout Interval, rhs: Interval) {
         lhs = lhs.adding(rhs)
     }
 
     /// Returns the additive inverse of the specified interval.
     public prefix static func - (interval: Interval) -> Interval {
-        return interval.opposite
+        return interval.negated
     }
 }
 
 // MARK: - Sugars
+
 extension Interval {
 
     /// Creates an interval from the given number of seconds.
@@ -245,6 +213,7 @@ public protocol IntervalConvertible {
 
 extension Int: IntervalConvertible {
 
+    /// Creates an interval from this amount of nanoseconds.
     public var nanoseconds: Interval {
         return Interval(nanoseconds: Double(self))
     }
@@ -252,6 +221,7 @@ extension Int: IntervalConvertible {
 
 extension Double: IntervalConvertible {
 
+    /// Creates an interval from this amount of nanoseconds.
     public var nanoseconds: Interval {
         return Interval(nanoseconds: self)
     }
@@ -259,80 +229,96 @@ extension Double: IntervalConvertible {
 
 extension IntervalConvertible {
 
+    // Alias for `nanoseconds`.
     public var nanosecond: Interval {
         return nanoseconds
     }
 
+    // Alias for `microseconds`.
     public var microsecond: Interval {
         return microseconds
     }
 
+    /// Creates an interval from this amount of microseconds.
     public var microseconds: Interval {
         return nanoseconds * pow(10, 3)
     }
 
+    /// Alias for `milliseconds`.
     public var millisecond: Interval {
         return milliseconds
     }
 
+    /// Creates an interval from this amount of milliseconds.
     public var milliseconds: Interval {
         return nanoseconds * pow(10, 6)
     }
 
+    /// Alias for `second`.
     public var second: Interval {
         return seconds
     }
 
+    /// Creates an interval from this amount of seconds.
     public var seconds: Interval {
         return nanoseconds * pow(10, 9)
     }
 
+    /// Alias for `minute`.
     public var minute: Interval {
         return minutes
     }
 
+    /// Creates an interval from this amount of minutes.
     public var minutes: Interval {
         return seconds * 60
     }
 
+    /// Alias for `hours`.
     public var hour: Interval {
         return hours
     }
 
+    /// Creates an interval from this amount of hours.
     public var hours: Interval {
         return minutes * 60
     }
 
+    /// Alias for `days`.
     public var day: Interval {
         return days
     }
 
+    /// Creates an interval from this amount of days.
     public var days: Interval {
         return hours * 24
     }
 
+    /// Alias for `weeks`.
     public var week: Interval {
         return weeks
     }
 
+    /// Creates an interval from this amount of weeks.
     public var weeks: Interval {
         return days * 7
     }
 }
 
 // MARK: - Date
+
 extension Date {
 
     /// The interval between this date and the current date and time.
     ///
-    /// If this date is earlier than now, this interval will be negative.
+    /// If this date is earlier than now, the interval will be negative.
     public var intervalSinceNow: Interval {
         return timeIntervalSinceNow.seconds
     }
 
     /// Returns the interval between this date and the given date.
     ///
-    /// If this date is earlier than the given date, this interval will be negative.
+    /// If this date is earlier than the given date, the interval will be negative.
     public func interval(since date: Date) -> Interval {
         return timeIntervalSince(date).seconds
     }
@@ -342,18 +328,19 @@ extension Date {
         return addingTimeInterval(interval.asSeconds())
     }
 
-    /// Returns a date with an interval added to it.
+    /// Returns a new date by adding an interval to the date.
     public static func + (lhs: Date, rhs: Interval) -> Date {
         return lhs.adding(rhs)
     }
 }
 
 // MARK: - DispatchSourceTimer
+
 extension DispatchSourceTimer {
 
     /// Schedule this timer later.
     func schedule(after timeout: Interval) {
-        guard !timeout.isNegative else { return }
+        if timeout.isNegative { return }
         let ns = timeout.nanoseconds.clampedToInt()
         schedule(wallDeadline: .now() + DispatchTimeInterval.nanoseconds(ns))
     }

Sources/Schedule/Monthday.swift

@@ -1,6 +1,6 @@
 import Foundation
 
-/// `Monthday` represents a day of a month.
+/// `Monthday` represents the combination of a month and day-of-month.
 public enum Monthday {
 
     case january(Int)
@@ -27,9 +27,9 @@ public enum Monthday {
 
     case december(Int)
 
-    /// Returns a dateComponenets of the monthday, using gregorian calender and
+    /// Returns a dateComponenets of this monthday, using gregorian calender and
     /// current time zone.
-    public func toDateComponents() -> DateComponents {
+    public func asDateComponents() -> DateComponents {
         var month, day: Int
         switch self {
         case .january(let n):       month = 1; day = n
@@ -49,16 +49,15 @@ public enum Monthday {
             calendar: Calendar.gregorian,
             timeZone: TimeZone.current,
             month: month,
-            day: day
+            day: day)
-        )
     }
 }
 
 extension Date {
 
-    /// Returns a boolean value indicating whether today is the monthday.
+    /// Returns a Boolean value indicating whether this date is the monthday.
     public func `is`(_ monthday: Monthday) -> Bool {
-        let components = monthday.toDateComponents()
+        let components = monthday.asDateComponents()
 
         let m = Calendar.gregorian.component(.month, from: self)
         let d = Calendar.gregorian.component(.day, from: self)
@@ -72,7 +71,7 @@ extension Monthday: CustomStringConvertible {
     ///
     ///     "Monthday: May 1st"
     public var description: String {
-        let components = toDateComponents()
+        let components = asDateComponents()
 
         let m = components.month!
         let d = components.day!

Sources/Schedule/Period.swift

@@ -1,6 +1,7 @@
 import Foundation
 
-/// `Period` represents a period of time defined in terms of fields.
+/// Type used to represents a date-based amount of time in the ISO-8601 calendar system,
+/// such as '2 years, 3 months and 4 days'.
 ///
 /// It's a little different from `Interval`:
 ///
@@ -51,48 +52,54 @@ public struct Period {
     ///     Period.registerQuantifier("fifty", for: 15)
     ///     let period = Period("fifty minutes")
     public static func registerQuantifier(_ word: String, for number: Int) {
-        quantifiers.write { $0[word] = number }
+        quantifiers.writeVoid { $0[word] = number }
     }
 
-    /// Creates a period from a natural expression.
+    /// Initializes a period from a natural expression.
     ///
-    ///     Period("one second") => Period(seconds: 1)
+    ///     Period("one second") -> Period(seconds: 1)
-    ///     Period("two hours and ten minutes") => Period(hours: 2, minutes: 10)
+    ///     Period("two hours and ten minutes") -> Period(hours: 2, minutes: 10)
-    ///     Period("1 year, 2 months and 3 days") => Period(years: 1, months: 2, days: 3)
+    ///     Period("1 year, 2 months and 3 days") -> Period(years: 1, months: 2, days: 3)
     public init?(_ string: String) {
-        var period = string
+        var str = string
         for (word, number) in Period.quantifiers.read({ $0 }) {
-            period = period.replacingOccurrences(of: word, with: "\(number)")
+            str = str.replacingOccurrences(of: word, with: "\(number)")
         }
-        guard let regex = try? NSRegularExpression(pattern: "( and |, )") else {
+        guard let regexp = try? NSRegularExpression(pattern: "( and |, )") else {
+            return nil
+        }
+        str = regexp.stringByReplacingMatches(in: str, range: NSRange(location: 0, length: str.count), withTemplate: "$")
+
+        var period = 0.year
+        for pair in str.split(separator: "$").map({ $0.split(separator: " ") }) {
+            guard
+                pair.count == 2,
+                let number = Int(pair[0])
+            else {
                 return nil
             }
-        period = regex.stringByReplacingMatches(in: period, range: NSRange(location: 0, length: period.count), withTemplate: "$")
             
-        var result = 0.year
-        for pair in period.split(separator: "$").map({ $0.split(separator: " ") }) {
-            guard pair.count == 2 else { return nil }
-            guard let number = Int(pair[0]) else { return nil }
             var unit = String(pair[1])
             if unit.last == "s" { unit.removeLast() }
             switch unit {
-            case "year":            result = result + number.years
+            case "year":            period = period + number.years
-            case "month":           result = result + number.months
+            case "month":           period = period + number.months
-            case "day":             result = result + number.days
+            case "day":             period = period + number.days
-            case "week":            result = result + (number * 7).days
+            case "week":            period = period + (number * 7).days
-            case "hour":            result = result + number.hours
+            case "hour":            period = period + number.hours
-            case "minute":          result = result + number.minutes
+            case "minute":          period = period + number.minutes
-            case "second":          result = result + number.second
+            case "second":          period = period + number.second
-            case "nanosecond":      result = result + number.nanosecond
+            case "nanosecond":      period = period + number.nanosecond
             default:                break
             }
         }
-        self = result.tidied(to: .day)
+        self = period
     }
 
-    /// Returns a new period by adding a period to this period.
+    /// Returns a new period by adding the given period to this period.
     public func adding(_ other: Period) -> Period {
-        return Period(years: years.clampedAdding(other.years),
+        return Period(
+            years: years.clampedAdding(other.years),
             months: months.clampedAdding(other.months),
             days: days.clampedAdding(other.days),
             hours: hours.clampedAdding(other.hours),
@@ -101,54 +108,57 @@ public struct Period {
             nanoseconds: nanoseconds.clampedAdding(other.nanoseconds))
     }
 
-    /// Returns a new period by adding an interval to this period.
+    /// Returns a new period by adding an interval to the period.
     public func adding(_ interval: Interval) -> Period {
         return Period(
             years: years, months: months, days: days,
             hours: hours, minutes: minutes, seconds: seconds,
-            nanoseconds: nanoseconds.clampedAdding(interval.nanoseconds.clampedToInt())
+            nanoseconds: nanoseconds.clampedAdding(interval.nanoseconds.clampedToInt()))
-        ).tidied(to: .day)
     }
 
-    /// Adds two periods and produces their sum.
+    /// Returns a new period by adding the right period to the left period.
+    ///
+    ///     Period(days: 1) + Period(days: 1) -> Period(days: 2)
     public static func + (lhs: Period, rhs: Period) -> Period {
         return lhs.adding(rhs)
     }
 
-    /// Returns a period with an interval added to it.
+    /// Returns a new period by adding an interval to the period.
     public static func + (lhs: Period, rhs: Interval) -> Period {
         return lhs.adding(rhs)
     }
 
-    /// Type to be used as tidying parameter.
+    /// Represents the tidy level.
-    public enum Unit {
+    public enum TideLevel {
         case day, hour, minute, second, nanosecond
     }
 
-    /// Returns a tidied period.
+    /// Returns the tidied period.
     ///
     ///     Period(hours: 25).tidied(to .day) => Period(days: 1, hours: 1)
-    public func tidied(to unit: Unit) -> Period {
+    public func tidied(to level: TideLevel) -> Period {
         var period = self
-        if case .nanosecond = unit { return period }
+        
+        if case .nanosecond = level { return period }
+        
         if period.nanoseconds.magnitude >= UInt(1.second.nanoseconds) {
             period.seconds += period.nanoseconds / Int(1.second.nanoseconds)
             period.nanoseconds %= Int(1.second.nanoseconds)
         }
+        if case .second = level { return period }
         
-        if case .second = unit { return period }
         if period.seconds.magnitude >= 60 {
             period.minutes += period.seconds / 60
             period.seconds %= 60
         }
+        if case .minute = level { return period }
         
-        if case .minute = unit { return period }
         if period.minutes.magnitude >= 60 {
             period.hours += period.minutes / 60
             period.minutes %= 60
         }
+        if case .hour = level { return period }
         
-        if case .hour = unit { return period }
         if period.hours.magnitude >= 24 {
             period.days += period.hours / 24
             period.hours %= 24
@@ -156,9 +166,9 @@ public struct Period {
         return period
     }
 
-    /// Returns a dateComponenets of the period, using gregorian calender and
+    /// Returns a dateComponenets of this period, using gregorian calender and
     /// current time zone.
-    public func toDateComponents() -> DateComponents {
+    public func asDateComponents() -> DateComponents {
         return DateComponents(year: years, month: months, day: days,
                               hour: hours, minute: minutes, second: seconds,
                               nanosecond: nanoseconds)
@@ -169,10 +179,10 @@ extension Date {
 
     /// Returns a new date by adding a period to this date.
     public func adding(_ period: Period) -> Date {
-        return Calendar.gregorian.date(byAdding: period.toDateComponents(), to: self) ?? .distantFuture
+        return Calendar.gregorian.date(byAdding: period.asDateComponents(), to: self) ?? .distantFuture
     }
 
-    /// Returns a date with a period added to it.
+    /// Returns a new date by adding a period to this date.
     public static func + (lhs: Date, rhs: Period) -> Date {
         return lhs.adding(rhs)
     }
@@ -180,18 +190,22 @@ extension Date {
 
 extension Int {
 
+    /// Creates a period from this amount of years.
     public var years: Period {
         return Period(years: self)
     }
 
+    /// Alias for `years`.
     public var year: Period {
         return years
     }
 
+    /// Creates a period from this amount of month.
     public var months: Period {
         return Period(months: self)
     }
 
+    /// Alias for `month`.
     public var month: Period {
         return months
     }

Sources/Schedule/Plan.swift

@@ -302,7 +302,7 @@ extension Plan {
             var last: Date!
             return AnyIterator {
                 last = last ?? Date()
-                guard let next = calendar.date(byAdding: period.toDateComponents(),
+                guard let next = calendar.date(byAdding: period.asDateComponents(),
                                                to: last) else {
                     return nil
                 }
@@ -410,7 +410,7 @@ extension Plan {
                 } else if Date().is(weekday) {
                     date = Date().startOfToday
                 } else {
-                    let components = weekday.toDateComponents()
+                    let components = weekday.asDateComponents()
                     date = calendar.nextDate(after: Date(), matching: components, matchingPolicy: .strict)
                 }
                 return date
@@ -450,7 +450,7 @@ extension Plan {
                 } else if Date().is(monthday) {
                     date = Date().startOfToday
                 } else {
-                    let components = monthday.toDateComponents()
+                    let components = monthday.asDateComponents()
                     date = calendar.nextDate(after: Date(), matching: components, matchingPolicy: .strict)
                 }
                 return date

Sources/Schedule/Task.swift

@@ -94,7 +94,7 @@ open class Task {
     }
 
     private func scheduleNext() {
-        _mutex.withLock {
+        _mutex.withLockVoid {
             let now = Date()
             var estimated = _timeline.estimatedNextExecution ?? now
             repeat {
@@ -155,7 +155,7 @@ open class Task {
 
     /// Reschedules this task with the new plan.
     public func reschedule(_ new: Plan) {
-        _mutex.withLock {
+        _mutex.withLockVoid {
             _iterator = new.makeIterator()
         }
         scheduleNext()
@@ -170,7 +170,7 @@ open class Task {
 
     /// Suspends this task.
     public func suspend() {
-        _mutex.withLock {
+        _mutex.withLockVoid {
             if _suspensions < UInt64.max {
                 _timer.suspend()
                 _suspensions += 1
@@ -180,7 +180,7 @@ open class Task {
 
     /// Resumes this task.
     public func resume() {
-        _mutex.withLock {
+        _mutex.withLockVoid {
             if _suspensions > 0 {
                 _timer.resume()
                 _suspensions -= 1
@@ -190,7 +190,7 @@ open class Task {
 
     /// Cancels this task.
     public func cancel() {
-        _mutex.withLock {
+        _mutex.withLockVoid {
             _timer.cancel()
         }
         TaskCenter.default.remove(self)
@@ -234,7 +234,9 @@ open class Task {
     /// - Returns: `true` if set successfully, `false` if not.
     @discardableResult
     public func setLifetime(_ interval: Interval) -> Bool {
-        guard restOfLifetime.isPositive else { return false }
+        if restOfLifetime.isNegative {
+            return false
+        }
 
         _mutex.lock()
         let age = Date().interval(since: _timeline.initialization)
@@ -258,10 +260,10 @@ open class Task {
     @discardableResult
     public func addLifetime(_ interval: Interval) -> Bool {
         var rest = restOfLifetime
-        guard rest.isPositive else { return false }
+        if rest.isNegative { return false }
         rest += interval
-        guard rest.isPositive else { return false }
+        if rest.isNegative { return false }
-        _mutex.withLock {
+        _mutex.withLockVoid {
             _lifetime += interval
             _lifetimeTimer.schedule(after: rest)
         }
@@ -276,7 +278,7 @@ open class Task {
     /// - Returns: `true` if set successfully, `false` if not.
     @discardableResult
     public func subtractLifetime(_ interval: Interval) -> Bool {
-        return addLifetime(interval.opposite)
+        return addLifetime(interval.negated)
     }
 
     // MARK: - Action
@@ -298,15 +300,15 @@ open class Task {
 
     /// Removes action by key from this task.
     public func removeAction(byKey key: ActionKey) {
-        _mutex.withLock {
+        _mutex.withLockVoid {
-            _ = _onElapseActions.delete(key.bagKey)
+            _ = _onElapseActions.removeValue(for: key.bagKey)
         }
     }
 
     /// Removes all actions from this task.
     public func removeAllActions() {
-        _mutex.withLock {
+        _mutex.withLockVoid {
-            _onElapseActions.clear()
+            _onElapseActions.removeAll()
         }
     }
 

Sources/Schedule/TaskCenter.swift

@@ -53,7 +53,7 @@ open class TaskCenter {
 
         task.taskCenterMutex.unlock()
 
-        mutex.withLock {
+        mutex.withLockVoid {
             let box = TaskBox(task)
             tagMap[box] = []
         }
@@ -75,7 +75,7 @@ open class TaskCenter {
 
         task.taskCenterMutex.unlock()
 
-        mutex.withLock {
+        mutex.withLockVoid {
             let box = TaskBox(task)
             if let tags = self.tagMap[box] {
                 for tag in tags {
@@ -99,7 +99,7 @@ open class TaskCenter {
     open func addTags(_ tags: [String], to task: Task) {
         guard task.taskCenter === self else { return }
 
-        mutex.withLock {
+        mutex.withLockVoid {
             let box = TaskBox(task)
             if tagMap[box] == nil {
                 tagMap[box] = []
@@ -127,7 +127,7 @@ open class TaskCenter {
     open func removeTags(_ tags: [String], from task: Task) {
         guard task.taskCenter === self else { return }
 
-        mutex.withLock {
+        mutex.withLockVoid {
             let box = TaskBox(task)
             for tag in tags {
                 tagMap[box]?.remove(tag)
@@ -170,7 +170,7 @@ open class TaskCenter {
 
     /// Removes all tasks in this center.
     open func clear() {
-        mutex.withLock {
+        mutex.withLockVoid {
             tagMap = [:]
             taskMap = [:]
         }

Sources/Schedule/Time.swift

@@ -15,9 +15,7 @@ public struct Time {
     /// Nanosecond of second.
     public let nanosecond: Int
 
-    /// Creates a time with `hour`, `minute`, `second` and `nanosecond` fields.
+    /// Initializes a time with `hour`, `minute`, `second` and `nanosecond`.
-    ///
-    /// If any parameter is illegal, return nil.
     ///
     ///     Time(hour: 11, minute: 11)  => "11:11:00.000"
     ///     Time(hour: 25)              => nil
@@ -36,34 +34,29 @@ public struct Time {
         self.nanosecond = nanosecond
     }
 
-    /// Creates a time with a string.
+    /// Initializes a time with a string.
     ///
-    /// If the parameter is illegal, return nil.
+    ///     Time("11") -> Time(hour: 11)
-    ///
+    ///     Time("11:12") -> Time(hour: 11, minute: 12)
-    ///     Time("11") == Time(hour: 11)
+    ///     Time("11:12:13") -> Time(hour: 11, minute: 12, second: 13)
-    ///     Time("11:12") == Time(hour: 11, minute: 12)
+    ///     Time("11:12:13.123") -> Time(hour: 11, minute: 12, second: 13, nanosecond: 123000000)
-    ///     Time("11:12:13") == Time(hour: 11, minute: 12, second: 13)
-    ///     Time("11:12:13.123") == Time(hour: 11, minute: 12, second: 13, nanosecond: 123000000)
     ///
     ///     Time("-1.0") == nil
     ///
-    /// Any of the previous examples can have a period suffix("am", "AM", "pm", "PM"),
-    /// separated by a space.
-    ///
     ///     Time("11 pm") == Time(hour: 23)
     ///     Time("11:12:13 PM") == Time(hour: 23, minute: 12, second: 13)
     public init?(_ string: String) {
         let pattern = "^(\\d{1,2})(:(\\d{1,2})(:(\\d{1,2})(.(\\d{1,3}))?)?)?( (am|AM|pm|PM))?$"
 
         guard let regexp = try? NSRegularExpression(pattern: pattern, options: []) else { return nil }
-        guard let result = regexp.matches(in: string, options: [], range: NSRange(location: 0, length: string.count)).first else { return nil }
+        guard let matches = regexp.matches(in: string, options: [], range: NSRange(location: 0, length: string.count)).first else { return nil }
 
         var hasAM = false
         var hasPM = false
         var values: [Int] = []
 
-        for i in 0..<result.numberOfRanges {
+        for i in 0..<matches.numberOfRanges {
-            let range = result.range(at: i)
+            let range = matches.range(at: i)
             if range.length == 0 { continue }
             let captured = NSString(string: string).substring(with: range)
             hasAM = ["am", "AM"].contains(captured)
@@ -94,7 +87,7 @@ public struct Time {
 
     /// Returns a dateComponenets of the time, using gregorian calender and
     /// current time zone.
-    public func toDateComponents() -> DateComponents {
+    public func asDateComponents() -> DateComponents {
         return DateComponents(calendar: Calendar.gregorian,
                               timeZone: TimeZone.current,
                               hour: hour,

Sources/Schedule/Weekday.swift

@@ -7,18 +7,17 @@ public enum Weekday: Int {
 
     /// Returns dateComponenets of the weekday, using gregorian calender and
     /// current time zone.
-    public func toDateComponents() -> DateComponents {
+    public func asDateComponents() -> DateComponents {
         return DateComponents(
             calendar: Calendar.gregorian,
             timeZone: TimeZone.current,
-            weekday: rawValue
+            weekday: rawValue)
-        )
     }
 }
 
 extension Date {
 
-    /// Returns a boolean value indicating whether this day is the weekday.
+    /// Returns a Boolean value indicating whether this date is the weekday.
     public func `is`(_ weekday: Weekday) -> Bool {
         return Calendar.gregorian.component(.weekday, from: self) == weekday.rawValue
     }

Tests/ScheduleTests/AtomicTests.swift

@@ -3,29 +3,42 @@ import XCTest
 
 final class AtomicTests: XCTestCase {
 
-    func testSnapshot() {
-        let i = Atomic<Int>(1)
-        XCTAssertEqual(i.snapshot(), 1)
-    }
-
     func testRead() {
         let i = Atomic<Int>(1)
-        i.read {
+        let val = i.read { $0 }
-            XCTAssertEqual($0, 1)
+        XCTAssertEqual(val, 1)
     }
+    
+    func testReadVoid() {
+        let i = Atomic<Int>(1)
+        var val = 0
+        i.read { val = $0 }
+        XCTAssertEqual(val, 1)
     }
 
     func testWrite() {
         let i = Atomic<Int>(1)
+        let val = i.write { v -> Int in
+            v += 1
+            return v
+        }
+        XCTAssertEqual(i.read { $0 }, val)
+    }
+    
+    func testWriteVoid() {
+        let i = Atomic<Int>(1)
+        var val = 0
         i.write {
             $0 += 1
+            val = $0
         }
-        XCTAssertEqual(i.snapshot(), 2)
+        XCTAssertEqual(i.read { $0 }, val)
     }
 
     static var allTests = [
-        ("testSnapshot", testSnapshot),
         ("testRead", testRead),
-        ("testWrite", testWrite)
+        ("testReadVoid", testReadVoid),
+        ("testWrite", testWrite),
+        ("testWriteVoid", testWriteVoid),
     ]
 }

Tests/ScheduleTests/BagTests.swift

@@ -15,66 +15,80 @@ final class BagTests: XCTestCase {
     }
 
     func testAppend() {
-        var cabinet = Bag<Fn>()
+        var bag = Bag<Fn>()
-        cabinet.append { 1 }
+        bag.append { 1 }
-        cabinet.append { 2 }
+        bag.append { 2 }
 
-        XCTAssertEqual(cabinet.count, 2)
+        XCTAssertEqual(bag.count, 2)
     }
 
-    func testGet() {
+    func testValueForKey() {
-        var cabinet = Bag<Fn>()
+        var bag = Bag<Fn>()
-        let k1 = cabinet.append { 1 }
+        let k1 = bag.append { 1 }
-        let k2 = cabinet.append { 2 }
+        let k2 = bag.append { 2 }
         
-        guard
+        let fn1 = bag.value(for: k1)
-            let fn1 = cabinet.get(k1),
-            let fn2 = cabinet.get(k2)
-        else {
-            XCTFail()
-            return
-        }
-        XCTAssertEqual(fn1(), 1)
-        XCTAssertEqual(fn2(), 2)
-    }
-
-    func testDelete() {
-        var cabinet = Bag<Fn>()
-
-        let k1 = cabinet.append { 1 }
-        let k2 = cabinet.append { 2 }
-
-        XCTAssertEqual(cabinet.count, 2)
-
-        let fn1 = cabinet.delete(k1)
         XCTAssertNotNil(fn1)
         
-        let fn2 = cabinet.delete(k2)
+        let fn2 = bag.value(for: k2)
         XCTAssertNotNil(fn2)
         
-        XCTAssertEqual(cabinet.count, 0)
+        guard let _fn1 = fn1, let _fn2 = fn2 else { return }
+        
+        XCTAssertEqual(_fn1(), 1)
+        XCTAssertEqual(_fn2(), 2)
     }
 
-    func testClear() {
+    func testRemoveValueForKey() {
-        var cabinet = Bag<Fn>()
+        var bag = Bag<Fn>()
 
-        cabinet.append { 1 }
+        let k1 = bag.append { 1 }
-        cabinet.append { 2 }
+        let k2 = bag.append { 2 }
 
-        XCTAssertEqual(cabinet.count, 2)
+        let fn1 = bag.removeValue(for: k1)
+        XCTAssertNotNil(fn1)
 
-        cabinet.clear()
+        let fn2 = bag.removeValue(for: k2)
-        XCTAssertEqual(cabinet.count, 0)
+        XCTAssertNotNil(fn2)
+        
+        guard let _fn1 = fn1, let _fn2 = fn2 else { return }
+        
+        XCTAssertEqual(_fn1(), 1)
+        XCTAssertEqual(_fn2(), 2)
+    }
+    
+    func testCount() {
+        var bag = Bag<Fn>()
+        
+        let k1 = bag.append { 1 }
+        let k2 = bag.append { 2 }
+        
+        XCTAssertEqual(bag.count, 2)
+        
+        bag.removeValue(for: k1)
+        bag.removeValue(for: k2)
+        
+        XCTAssertEqual(bag.count, 0)
+    }
+
+    func testRemoveAll() {
+        var bag = Bag<Fn>()
+
+        bag.append { 1 }
+        bag.append { 2 }
+
+        bag.removeAll()
+        XCTAssertEqual(bag.count, 0)
     }
 
     func testSequence() {
-        var cabinet = Bag<Fn>()
+        var bag = Bag<Fn>()
-        cabinet.append { 0 }
+        bag.append { 0 }
-        cabinet.append { 1 }
+        bag.append { 1 }
-        cabinet.append { 2 }
+        bag.append { 2 }
 
         var i = 0
-        for fn in cabinet {
+        for fn in bag {
             XCTAssertEqual(fn(), i)
             i += 1
         }
@@ -83,9 +97,10 @@ final class BagTests: XCTestCase {
     static var allTests = [
         ("testBagKey", testBagKey),
         ("testAppend", testAppend),
-        ("testGet", testGet),
+        ("testValueForKey", testValueForKey),
-        ("testDelete", testDelete),
+        ("testRemoveValueForKey", testRemoveValueForKey),
-        ("testClear", testClear),
+        ("testCount", testCount),
+        ("testRemoveAll", testRemoveAll),
         ("testSequence", testSequence)
     ]
 }

Tests/ScheduleTests/DateTimeTests.swift

@@ -6,9 +6,8 @@ final class DateTimeTests: XCTestCase {
     func testInterval() {
 
         XCTAssertTrue((-1).second.isNegative)
-        XCTAssertTrue(1.second.isPositive)
+        XCTAssertEqual(1.1.second.abs, 1.1.second)
-        XCTAssertEqual(1.1.second.magnitude, 1.1.second.nanoseconds)
+        XCTAssertEqual(1.second.negated, (-1).second)
-        XCTAssertEqual(1.second.opposite, (-1).second)
 
         XCTAssertEqual(7.day.hashValue, 1.week.hashValue)
         XCTAssertEqual(7.day, 1.week)
@@ -21,10 +20,6 @@ final class DateTimeTests: XCTestCase {
 
         XCTAssertTrue(1.1.second.isLonger(than: 1.0.second))
         XCTAssertTrue(3.days.isShorter(than: 1.week))
-        XCTAssertEqual(Interval.longest(1.hour, 1.day, 1.week), 1.week)
-        XCTAssertEqual(Interval.longest([]), nil)
-        XCTAssertEqual(Interval.shortest(1.hour, 59.minutes, 2999.seconds), 2999.seconds)
-        XCTAssertEqual(Interval.shortest([]), nil)
 
         XCTAssertEqual(1.second * 60, 1.minute)
         XCTAssertEqual(59.minutes + 60.seconds, 1.hour)
@@ -55,18 +50,18 @@ final class DateTimeTests: XCTestCase {
         let d = Date(year: 2019, month: 1, day: 1)
         XCTAssertTrue(d.is(.january(1)))
 
-        XCTAssertEqual(Monthday.january(1).toDateComponents().month, 1)
+        XCTAssertEqual(Monthday.january(1).asDateComponents().month, 1)
-        XCTAssertEqual(Monthday.february(1).toDateComponents().month, 2)
+        XCTAssertEqual(Monthday.february(1).asDateComponents().month, 2)
-        XCTAssertEqual(Monthday.march(1).toDateComponents().month, 3)
+        XCTAssertEqual(Monthday.march(1).asDateComponents().month, 3)
-        XCTAssertEqual(Monthday.april(1).toDateComponents().month, 4)
+        XCTAssertEqual(Monthday.april(1).asDateComponents().month, 4)
-        XCTAssertEqual(Monthday.may(1).toDateComponents().month, 5)
+        XCTAssertEqual(Monthday.may(1).asDateComponents().month, 5)
-        XCTAssertEqual(Monthday.june(1).toDateComponents().month, 6)
+        XCTAssertEqual(Monthday.june(1).asDateComponents().month, 6)
-        XCTAssertEqual(Monthday.july(1).toDateComponents().month, 7)
+        XCTAssertEqual(Monthday.july(1).asDateComponents().month, 7)
-        XCTAssertEqual(Monthday.august(1).toDateComponents().month, 8)
+        XCTAssertEqual(Monthday.august(1).asDateComponents().month, 8)
-        XCTAssertEqual(Monthday.september(1).toDateComponents().month, 9)
+        XCTAssertEqual(Monthday.september(1).asDateComponents().month, 9)
-        XCTAssertEqual(Monthday.october(1).toDateComponents().month, 10)
+        XCTAssertEqual(Monthday.october(1).asDateComponents().month, 10)
-        XCTAssertEqual(Monthday.november(1).toDateComponents().month, 11)
+        XCTAssertEqual(Monthday.november(1).asDateComponents().month, 11)
-        XCTAssertEqual(Monthday.december(1).toDateComponents().month, 12)
+        XCTAssertEqual(Monthday.december(1).asDateComponents().month, 12)
     }
 
     func testPeriod() {
@@ -113,7 +108,7 @@ final class DateTimeTests: XCTestCase {
             XCTAssertTrue(i.isAlmostEqual(to: (0.456.second.nanoseconds).nanoseconds, leeway: 0.001.seconds))
         }
 
-        let components = t1?.toDateComponents()
+        let components = t1?.asDateComponents()
         XCTAssertEqual(components?.hour, 11)
         XCTAssertEqual(components?.minute, 12)
         XCTAssertEqual(components?.second, 13)
@@ -140,7 +135,7 @@ final class DateTimeTests: XCTestCase {
         let d = Date(year: 2019, month: 1, day: 1)
         XCTAssertTrue(d.is(.tuesday))
 
-        XCTAssertEqual(Weekday.monday.toDateComponents().weekday!, 2)
+        XCTAssertEqual(Weekday.monday.asDateComponents().weekday!, 2)
     }
 
     static var allTests = [

Tests/ScheduleTests/DeinitObserverTests.swift

@@ -5,9 +5,9 @@ import XCTest
 
 final class DeinitObserverTests: XCTestCase {
 
-    func testObserver() {
+    func testObserve() {
         var i = 0
-        var fn = {
+        let fn = {
             let obj = NSObject()
             DeinitObserver.observe(obj) {
                 i += 1
@@ -15,8 +15,11 @@ final class DeinitObserverTests: XCTestCase {
         }
         fn()
         XCTAssertEqual(i, 1)
+    }
     
-        fn = {
+    func testCancel() {
+        var i = 0
+        let fn = {
             let obj = NSObject()
             let observer = DeinitObserver.observe(obj) {
                 i += 1
@@ -24,11 +27,12 @@ final class DeinitObserverTests: XCTestCase {
             observer.cancel()
         }
         fn()
-        XCTAssertEqual(i, 1)
+        XCTAssertEqual(i, 0)
     }
 
     static var allTests = [
-        ("testObserver", testObserver)
+        ("testObserve", testObserve),
+        ("testCancel", testCancel)
     ]
 }
 

Tests/ScheduleTests/ExtensionsTests.swift

@@ -16,11 +16,6 @@ final class ExtensionsTests: XCTestCase {
         XCTAssertEqual(i.clampedAdding(1), Int.max)
     }
 
-    func testClampedSubtracting() {
-        let i = Int.min
-        XCTAssertEqual(i.clampedSubtracting(1), Int.min)
-    }
-
     func testStartOfToday() {
         let components = Date().startOfToday.dateComponents
         guard
@@ -39,7 +34,6 @@ final class ExtensionsTests: XCTestCase {
     static var allTests = [
         ("testClampedToInt", testClampedToInt),
         ("testClampedAdding", testClampedAdding),
-        ("testClampedSubtracting", testClampedSubtracting),
         ("testStartOfToday", testStartOfToday)
     ]
 }

Tests/ScheduleTests/Helpers.swift

@@ -26,7 +26,7 @@ extension Date {
 extension Interval {
 
     func isAlmostEqual(to interval: Interval, leeway: Interval) -> Bool {
-        return (interval - self).magnitude <= leeway.magnitude
+        return (interval - self).abs <= leeway.abs
     }
 }
 

Tests/ScheduleTests/PlanTests.swift

@@ -9,8 +9,6 @@ final class PlanTests: XCTestCase {
         let intervals = [1.second, 2.hours, 3.days, 4.weeks]
         let s0 = Plan.of(intervals[0], intervals[1], intervals[2], intervals[3])
         XCTAssertTrue(s0.makeIterator().isAlmostEqual(to: intervals, leeway: leeway))
-        let s1 = Plan.from(intervals)
-        XCTAssertTrue(s1.makeIterator().isAlmostEqual(to: intervals, leeway: leeway))
 
         let d0 = Date() + intervals[0]
         let d1 = d0 + intervals[1]
@@ -42,15 +40,15 @@ final class PlanTests: XCTestCase {
     func testConcat() {
         let s0: [Interval] = [1.second, 2.minutes, 3.hours]
         let s1: [Interval] = [4.days, 5.weeks]
-        let s3 = Plan.from(s0).concat(Plan.from(s1))
+        let s3 = Plan.of(s0).concat(Plan.of(s1))
-        let s4 = Plan.from(s0 + s1)
+        let s4 = Plan.of(s0 + s1)
         XCTAssertTrue(s3.isAlmostEqual(to: s4, leeway: leeway))
     }
 
     func testMerge() {
         let intervals0: [Interval] = [1.second, 2.minutes, 1.hour]
         let intervals1: [Interval] = [2.seconds, 1.minutes, 1.seconds]
-        let scheudle0 = Plan.from(intervals0).merge(Plan.from(intervals1))
+        let scheudle0 = Plan.of(intervals0).merge(Plan.of(intervals1))
         let scheudle1 = Plan.of(1.second, 1.second, 1.minutes, 1.seconds, 58.seconds, 1.hour)
         XCTAssertTrue(scheudle0.isAlmostEqual(to: scheudle1, leeway: leeway))
     }