Extensions

Overview

As you know one of the main features of Swift is to be type safe, which basically means that you can’t use a variable inappropriately for the terms of its type. In other words, according to the rules of type safety, you can divide by zero — that’s not a type error — but you can’t perform an arithmetic operation with a string unless you do some conversions first.

In order to make a more Swift-like environment lots of Foundation classes are now typesafe since Swift3.

SwiftDate introduces three new enum which allows you to instantiate TimeZone, Calendar and Locale in a more safe way.

Calendar Shortcut: CalendarName

CalendarName is an enum which define all possible values for Calendar object.

The only property of CalendarName is .calendar: by calling it you will get the appropriate instance of Calendar object.

Examples

TimeZone Shortcut: TimeZoneName

TimeZoneName is an enum which define all pre-defined possible values for TimeZone objects.

The only property of TimeZoneName is .timezone: by calling it you will get the appropriate instance of TimeZone object.

Examples

Locale Shortcut: LocaleName

LocaleName is an enum which define all pre-defined possible values for LocaleName objects.

The only property of LocaleName is .locale: by calling it you will get the appropriate instance of Locale object.

Examples

TimeInterval

TimeInterval is a typealias used to measure the number of seconds.

SwiftDate introduces two extra functions for this type of object:

• .in(components: [Calendar.Component], of: CalendarName) function: it allows to express a time interval in one or more time components unit
• .string(options: ComponentsFormatterOptions) function: it allows to express a time interval in a string of components units

Examples

DateComponents

DateComponents in SwiftDate contains several extensions

First of all DateComponents contains a property for each time unit; this allows SwiftDate to support math operators between Date/DateInRegion and time components: let newDate = beforeDate + 2.days - 4.months + 3.hours

Moreover there are the following functions:

Create date by adding components from a Date or DateInRegion

• .from(date: Date, in region: Region? = nil) function: Create a new Date in absolute time from a specific date by adding self components
• .from(dateInRegion: DateInRegion) -> DateInRegion? function: Create a new DateInRegion from another DateInRegion by adding self components

Create date by subtracting components from a Date or DateInRegion

• .ago(from date: Date, in region: Region? = nil) -> Date? function: Create a new DateInRegion from another DateInRegion by subtracting self components
• .ago(fromDateInRegion date: DateInRegion) -> DateInRegion? function: Create a new DateInRegion from another DateInRegion by subtracting self components

Create date by adding/subtracting components from current datetime (both for Date and DateInRegion)

• .fromNow(in region: Region? = nil) -> Date? function: Create a new Date in absolute time from current date by adding self components
• .ago(in region: Region? = nil) -> Date? function: Create a new DateInRegion from current by subtracting self components