rjchatfield

import PlaygroundSupport
import SwiftUI

Grid.easy // 8ms
Grid.medium // 356ms
Grid.hard // 103ms
Grid.expert // 54,426ms
Grid.empty // 101ms
Grid.solved // 0ms
Grid.unsolvable // 0ms

rjchatfield

// MARK: - Either Attempt 1 - FAIL!
struct EitherAttempt1 {
    @State var state: ThreewayState
    
    func either<V1: View, V2: View>(block: () -> (V1?, V2?))  -> some View {
        TupleView<(V1?, V2?)>(block())
    }
    func either<V1: View, V2: View, V3: View>(block: () -> (V1?, V2?, V3?))  -> some View {
        TupleView<(V1?, V2?, V3?)>(block())
    }

rjchatfield

/// Rip off of the JavaScript implementation of:
/// https://github.com/LeaVerou/contrast-ratio/blob/gh-pages/color.js
extension UIColor {
    
    typealias Contrast = (ratio: CGFloat, error: CGFloat, min: CGFloat, max: CGFloat)
    
    /// Range: 1 ... 21
    func contrast(_ other: UIColor) -> Contrast {
        var other = other
        

rjchatfield

func doNothing(_: inout String) { /* do nothing!! */ }

var value = "foo" {
    didSet { print("didSet") }
}

doNothing(&value) // Unfortunately, triggers didSet!

var proxy: String {
    get { value }

rjchatfield

import Combine

extension Publisher {
    
    public func flatMap<T, P, UP>(
        maxPublishers: Subscribers.Demand = .unlimited,
        transform: @escaping (Self.Output) -> P,
        until: @autoclosure @escaping () -> UP
    ) -> Publishers.FlatMap<Publishers.PrefixUntilOutput<P, UP>, Self>
        where T == P.Output, P: Publisher, Self.Failure == P.Failure, UP: Publisher {

rjchatfield

const ComponentsWithRenderProps = () => (
<ComponentA value={'Value'}>
    {({ data, doSomethingWithComponentA }) => (
    <ComponentB value={'B-value'}>
        {something => (
        <ComponentC
            data={data}
            something={something}
            onAnotherThing={doSomethingWithComponentA}
        />

rjchatfield

// Line 109 is where the magic is!

import Foundation
import XCPlayground

func setInterval(seconds interval: Int, f: ()->()) {
    let delta = Int64(1) * Int64(NSEC_PER_SEC)
    let time = dispatch_time(DISPATCH_TIME_NOW, delta)

    dispatch_after(time, dispatch_get_main_queue(), {

rjchatfield

Types are coming

Last week I had a crash course in PureScript - a Haskell-like language that compiles to JavaScript. I’m not about to preach that you should write your web apps in Haskell (though I strongly recommend learning Haskell), however, I do wish to explore an important part of any Functional Programming language that has eluded Javascript...

Types.

There is a lot to be said about Javascript and its lack of static typing. We’ve built the whole web with it! But this post will explore the benefits of a compile-time strong static type system.

“But Javascript does have types!?”

rjchatfield

import Foundation

typealias RegexPattern = String

let aussiePhoneNumber = 0424_555_123
let brokePhoneNumber = 0424_555_1231

enum PhoneNumberType: RegexPattern {
    // List all regex patterns
    case AussieMobile = "(?:\\+?61|0)4(?:[01]\\d{3}|(?:2[1-9]|3[0-57-9]|4[7-9]|5[0-15-9]|6[679]|7[3-8]|8[1478]|9[07-9])\\d{2}|(?:20[2-9]|444|52[0-6]|68[3-9]|70[0-7]|79[01]|820|890|91[0-4])\\d|(?:200[0-3]|201[01]|8984))\\d{4}$"

rjchatfield

// ACTIONS & REDUCERS
enum CounterAction {
    case Increment
    case Decrement
    case ChangeBy(Int)
}
enum NameAction {
    case Set(String)
    case Clear
}