# OptionalExtensions
[](https://cocoapods.org/)
[](https://developer.apple.com/swift/)
[](https://opensource.org/licenses/MIT)
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](https://github.com/RuiAAPeres/OptionalExtensions#filter-wrapped---bool---optionalwrapped)
* [mapNil](https://github.com/RuiAAPeres/OptionalExtensions#mapnil-void---wrapped---optionalwrapped)
* [flatMapNil](https://github.com/RuiAAPeres/OptionalExtensions#flatmapnil-void---optionalwrapped---optionalwrapped)
* [then](https://github.com/RuiAAPeres/OptionalExtensions#then-wrapped---void---void-similar-to-ts-foreach)
* [maybe](https://github.com/RuiAAPeres/OptionalExtensions#maybe-u---wrapped---u---u-similar-to-haskells-maybe)
* [onSome](https://github.com/RuiAAPeres/OptionalExtensions#onsome-wrapped---void---optionalwrapped-injects-a-side-effect-in-the-some-branch)
* [onNone](https://github.com/RuiAAPeres/OptionalExtensions#onnone-void---void---optionalwrapped-injects-a-side-effect-in-the-none-branch)
* [isSome](https://github.com/RuiAAPeres/OptionalExtensions#issome-bool)
* [isNone](https://github.com/RuiAAPeres/OptionalExtensions#isnone-bool)
#### `filter: (Wrapped -> Bool) -> Optional`
```swift
let number: Int? = 3
let biggerThan2 = number.filter { $0 > 2 } // .Some(3)
let biggerThan3 = number.filter { $0 > 3 } // .None
```
#### `mapNil: (Void -> Wrapped) -> Optional`
```swift
let number: Int? = 3
number.mapNil { 2 } // .Some(3)
let nilledNumber: Int? = nil
nilledNumber.mapNil { 2 } // .Some(2)
```
#### `flatMapNil: (Void -> Optional) -> Optional`
```swift
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`)
```swift
let number: Int? = 3
number.then { print($0) } // prints "3"
let nilledNumber: Int? = nil
nilledNumber.then { print($0) } // print won't be called
```
#### `maybe: U -> (Wrapped -> U) -> U` (similar to Haskell's `maybe`)
```swift
let number: Int? = 3
number.maybe(100) { $0 + 1 } // 4
let nilledNumber: Int? = nil
nilledNumber.maybe(100) { $0 + 1 } // 100
```
#### `onSome: (Wrapped -> Void) -> Optional` (injects a side effect in the `.Some` branch)
```swift
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) } // .None
```
#### `onNone: (Void -> Void) -> Optional` (injects a side effect in the `.None` branch)
```swift
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 .None
```
#### `isSome: Bool`
```swift
let number: Int? = 3
let isSome = number.isSome // true
let nilledNumber: Int? = nil
let isSome = nilledNumber.isSome // false
```
#### `isNone: Bool`
```swift
let number: Int? = 3
let isSome = number.isNone // false
let nilledNumber: Int? = nil
let isSome = nilledNumber.isNone // true
```
Setup
-----
**Carthage:**
```
github "RuiAAPeres/OptionalExtensions"
```
**CocoaPods:**
```
pod "OptionalExtensions"
```
**Manually:**
Grab the [OptionalExtensions.swift](https://github.com/RuiAAPeres/OptionalExtensions/blob/master/OptionalExtensions/Source/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](LICENSE)
Copyright (c) 2015 Rui Peres