OptionalExtensions
Why?
Swift's Optional is pretty awesome, but it can always get better. This repository is an humble attempt to add some utility methods to it.
Operators
filter: (Wrapped -> Bool) -> Optional<Wrapped>
let number: Int? = 3
let biggerThan2 = number.filter { $0 > 2 } // .Some(3)
let biggerThan3 = number.filter { $0 > 3 } // .NonemapNil: (Void -> Wrapped) -> Optional<Wrapped>
let number: Int? = 3
number.mapNil { 2 } // .Some(3)
let nilledNumber: Int? = nil
nilledNumber.mapNil { 2 } // .Some(2)flatMapNil: (Void -> Optional<Wrapped>) -> Optional<Wrapped>
let number: Int? = 3
number.flatMapNil { .Some(2) } // .Some(3)
let nilledNumber: Int? = nil
nilledNumber.flatMapNil { .Some(2) } // .Some(2)then: (Wrapped -> Void) -> Void (similar to [T]'s forEach)
let number: Int? = 3
number.then { print($0) } // prints "3"
let nilledNumber: Int? = nil
nilledNumber.then { print($0) } // print won't be calledmaybe: U -> (Wrapped -> U) -> U (similar to Haskell's maybe)
let number: Int? = 3
number.maybe(100) { $0 + 1 } // 4
let nilledNumber: Int? = nil
nilledNumber.maybe(100) { $0 + 1 } // 100onSome: (Wrapped -> Void) -> Optional<Wrapped> (injects a side effect in the .Some branch)
let number: Int? = 3
let sameNumber = number.onSome { print($0) } // prints "3" & returns .Some(3)
let nilledNumber: Int? = nil
let sameNilledNumber = nilledNumber.onSome { print($0) } // .NoneonNone: (Void -> Void) -> Optional<Wrapped> (injects a side effect in the .None branch)
let number: Int? = 3
let sameNumber = number.onNone { print("Hello World") } // .Some(3)
let nilledNumber: Int? = nil
let sameNilledNumber = nilledNumber.onNone { print("Hello World") } // prints "Hello World" & returns .NoneisSome: Bool
let number: Int? = 3
let isSome = number.isSome // true
let nilledNumber: Int? = nil
let isSome = nilledNumber.isSome // falseisNone: Bool
let number: Int? = 3
let isSome = number.isNone // false
let nilledNumber: Int? = nil
let isSome = nilledNumber.isNone // trueSetup
Carthage:
github "RuiAAPeres/OptionalExtensions"
CocoaPods:
pod "OptionalExtensions"
Manually:
Grab the OptionalExtensions.swift file and drop it in your project.
Contributing
We will gladly accept Pull Requests with new methods or improving the ones that already exist. Documentation, or tests, are always welcome as well.
License
OptionalExtensions is licensed under the MIT License, Version 2.0. View the license file
Copyright (c) 2015 Rui Peres