nicklockwood

// ShapeScript document

detail 32

define roundedcube {
    option radius 0.25
    option size 1 1 1
    detail max(4 detail)
    define size_ size
    define diameter radius * 2 / size_

nicklockwood

import SwiftUI

enum OSDocumentError: Error {
    case unknownFileFormat
}

#if canImport(UIKit)

import UIKit

nicklockwood

import Foundation

// Here's a pretty typical scenario where you want to encode a polymorphic type -
// in this case a Shape type that can be either a Square or Circle. Swift provides
// a nice pattern for doing this in a type-safe way using enums:

struct Circle: Codable {
    var radius: Int
}

nicklockwood

import UIKit

extension UITextField {
    /// Add a trailing placeholder label that tracks the text as it changes
    func addTrailingPlaceholder(_ placeholder: String) {
        let label = UILabel()
        label.text = placeholder
        label.alpha = 0.3
        label.isHidden = true
        let container = UIView()

nicklockwood

// A quick test to compare performance of different dictionary lookups in Swift.
// Note: Results recorded on a 2020 M1 MBP. be sure to run with "Optimize for Speed [-O]

import Foundation

let iterations = 1000000

var dictionary = [Int: Int]()
for i in 0 ..< iterations {
    dictionary[i] = Int.random(in: 0 ..< 1000)

nicklockwood

// This gist demonstrates how you can implement versioning for a Codable struct to support loading
// old serialized data after changing the structure. Notable features of this solution:
//
// * No need to make new properties optional, or to perform post-processing on the struct after
//   loading in ordeer to populate missing values
// * No need to change the call site - from the outside this struct behaves just the same
//   as if we had implemented codable directly in the normal way.
// * Versioning can be applied individually to parents or leaves in a larger tree of
//   structs without affecting the other elements
// * This approach will work even if the original struct was not designed with versioning in mind

nicklockwood

extension Data {
  init?(hexString: String) {
    let count = hexString.count / 2
    var data = Data(capacity: count)
    var i = hexString.startIndex
    for _ in 0 ..< count {
      let j = hexString.index(after: i)
      if var byte = UInt8(hexString[i ... j], radix: 16) {
        data.append(&byte, count: 1)
      } else {

nicklockwood

import UIKit

// Create color using P3 color space
let linearColor = UIColor(displayP3Red: 1, green: 0.5, blue: 0.2, alpha: 1)

do {
    var r: CGFloat = 0, g: CGFloat = 0, b: CGFloat = 0, a: CGFloat = 0
    linearColor.getRed(&r, green: &g, blue: &b, alpha: &a)
    print(r, g, b, a) // 1.07, 0.46, 0.0, 1.0 - not the expected values
}

nicklockwood

/// The Jaro-Winkler edit distance between two strings (0 - 1)
func editDistance(_ lhs: String, _ rhs: String) -> Double {
    return 1 - jaroWinklerSimilarity(Array(lhs), Array(rhs))
}

/// Jaro-Winkler similarity between two strings (0 - 1)
/// https://www.geeksforgeeks.org/jaro-and-jaro-winkler-similarity/
private func jaroWinklerSimilarity(_ s1: [Character], _ s2: [Character]) -> Double {
    var jaro = jaroSimilarity(s1, s2)

nicklockwood

import Foundation

enum LexingError: Error, Equatable {
  case syntaxError(String)
  case unexpectedEOF
}

enum ParsingError: Error {
  case expected(String)
  case unexpectedToken(Token)