IGListKit/Examples/Examples-macOS/IGListKitExamples/Helpers/Shuffle.swift
Guilherme Rambo 47fbb72fa6 macOS example app
Summary:
Related issue: #333

I've made a very simple macOS example app. It's just a list of names which can be searched, shuffled or deleted.

I think this is a good starting point for anyone who wants to use this on macOS projects :)

![iglistkitmac](https://cloud.githubusercontent.com/assets/67184/21238494/7245f242-c2ea-11e6-98ea-218a6150d14c.gif)
Closes https://github.com/Instagram/IGListKit/pull/337

Reviewed By: rnystrom

Differential Revision: D4345236

Pulled By: jessesquires

fbshipit-source-id: ce75372263d3f451e34f2c816c14ab6bc82116a7
2016-12-19 10:59:03 -08:00

46 lines
1.5 KiB
Swift

/**
Copyright (c) 2016-present, Facebook, Inc. All rights reserved.
The examples provided by Facebook are for non-commercial testing and evaluation
purposes only. Facebook reserves all rights not expressly granted.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
FACEBOOK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
import Foundation
extension MutableCollection where Indices.Iterator.Element == Index {
/// Shuffles the contents of this collection.
mutating func shuffle() {
let c = count
guard c > 1 else { return }
for (firstUnshuffled , unshuffledCount) in zip(indices, stride(from: c, to: 1, by: -1)) {
let d: IndexDistance = numericCast(arc4random_uniform(numericCast(unshuffledCount)))
guard d != 0 else { continue }
let i = index(firstUnshuffled, offsetBy: d)
swap(&self[firstUnshuffled], &self[i])
}
}
}
extension Sequence {
/// Returns an array with the contents of this sequence, shuffled.
var shuffled: [Iterator.Element] {
var result = Array(self)
result.shuffle()
return result
}
}