 	func subtract(_ timeChunk: TimeChunk) -> Date {
 		return Date()
 	}
+    
+    func add(_ timeInterval: TimeInterval) -> Date {
+        return Date()
+    }
+    
+    func subtract(_ timeInterval: TimeInterval) -> Date {
+        return Date()
+    }
 	
 	// MARK: - Time Between
 	
 	func timeBetween(date: Date) -> TimeInterval {
 		return TimeInterval()
 	}
+    
+    func chunkBetween(date: Date) -> TimeChunk {
+        return TimeChunk()
+    }
 	
 	
 	// MARK: - Comparisons

	static func -(minuend: Date, subtrahend: TimeChunk) -> Date {
		return minuend.subtract(subtrahend)
	}
}

		return self.compare(date) == .orderedAscending
	}
	
    
	// MARK: - Operator Overloads
	
	static func +(leftAddend: Date, rightAddend: TimeChunk) -> Date {
