daehn’s gists

daehn / optional-assignment.swift

Last active August 29, 2015 14:27 — forked from radex/optional-assignment.swift

Optional assignment operator implementation. `foo ?= bar` will evaluate and assign bar to foo if and only if foo is nil. Equivalent to `||=` in Ruby and other languages.

	infix operator ?= {
	associativity right
	precedence 90
	assignment
	}

	func ?=<T>(inout variable: T?, expr: @autoclosure () -> T) {
	if variable == nil {
	variable = expr()
	}

daehn / Subset.swift

Last active August 29, 2015 14:27

Finds the largest ascending subset and their indices contained in an Array<Int>

	import Foundation

	typealias IndexedSlice = (slice: ArraySlice<Int>, index: Int)
	let ascending: (Int, Int) -> Bool = { $0 < $1 }

	func solution(input: [Int]) -> [Int] {
	assert(input.count > 0, "Cannot calculate for empty array")
	return largestAscendingSlicesWithIndex(input).map { $0.index }
	}

daehn / FibonacciGenerator.swift

Last active August 25, 2015 22:19

Swift Generator that produces Fibonacci numbers

	import UIKit

	struct FibonacciGenerator: GeneratorType, SequenceType {

	var (f1, f2) = (1, 1)

	mutating func next() -> Int? {
	let result = f1
	(f1, f2) = (f2, f1 + f2)
	return result

daehn / CDHelper.swift

Last active August 31, 2015 15:20

Small NSManagedObject extension to simplify fetching and creating objects.

	import Foundation
	import CoreData

	extension NSManagedObject {

	class var entityName: String {
	return NSStringFromClass(self).componentsSeparatedByString(".").last!
	}

	convenience init(context: NSManagedObjectContext) {

daehn / Levenshtein.swift

Last active August 28, 2017 02:19

Calculate the Levenshtein-Distance between two Strings in Swift


	extension String {

	subscript(index: Int) -> Character {
	return self[startIndex.advancedBy(index)]
	}

	subscript(range: Range<Int>) -> String {
	let start = startIndex.advancedBy(range.startIndex)
	let end = startIndex.advancedBy(range.endIndex)

daehn / EnumReflection.swift

Last active September 2, 2015 22:16

	enum Beat {
	case NoBeat, BPM(Int), Other(Int)
	var value : Int? {
	return Mirror(reflecting: self).children.first?.value as? Int
	}
	}

	let enums: [Beat] = [.NoBeat, .BPM(105), .Other(120)]
	enums.forEach { print($0.value) }

daehn / First.swift

Created September 12, 2015 16:05

	extension SequenceType {
	func first(@noescape predicate: Generator.Element -> Bool) -> Generator.Element? {
	for element in self {
	if predicate(element) {
	return element
	}
	}
	return nil
	}
	}

daehn / script.swift

Last active September 18, 2015 17:41 — forked from zats/script.swift

Update all your plugins for the latest Xcode beta with a single

	#!/usr/bin/env xcrun swift

	// $ chmod +x script.swift
	// $ ./script.swift
	// or $ ./script.swift -xcode=/Applications/Xcode-beta.app

	import Foundation

	@noreturn private func failWithError(message: String) {
	print("🚫 \(message)")

daehn / Searchable.swift

Last active April 23, 2019 03:05

Swift protocols and protocol extensions to easily add and delete conforming instances to Spotlight. Blog post can be found here: http://silvandaehn.com/2015/09/25/Simplifying-CoreSpotlight/

	import UIKit
	import CoreSpotlight
	import MobileCoreServices

	public typealias Completion = NSError? -> Void

	// MARK: - Searchable Protocol

	public protocol Searchable {
	static var spotlightDomainIdentifier: String { get }

daehn / CountElement.Swift

Last active January 30, 2016 19:50

Extension on SequenceType to count the occurrence of an element.

	extension SequenceType where Generator.Element : Equatable {
	func count(other: Generator.Element) -> Int {
	var sum = 0
	for case other in self { sum++ }
	return sum
	}
	}

	func ~=<T>(pattern: T -> Bool, value: T) -> Bool {
	return pattern(value)

Silvan Dähn daehn