DanielCardonaRojas

import Foundation

// MARK: - Getting substrings
// String API lacks take(while:) and suffix(while:) but has drop(while:) and prefix(while:)
extension String {
    func prefix(while predicate: (Unicode.Scalar) -> Bool) -> Substring {
        return self.prefix(while: { (c: Character) -> Bool in
            return c.unicodeScalars.contains(where: predicate)
        })
    }

DanielCardonaRojas

/* -------------- Higher order function combinators ---------------- */
// Composition operators

infix operator >>>
func >>> <A,B,C> (aToB: @escaping (A) -> B, bToC: @escaping (B) -> C) -> (A) -> C {
    return { a in aToB(a) |> bToC }
}

infix operator <<<
func <<< <A,B,C> (bToC: @escaping (B) -> C, aToB: @escaping (A) -> B) -> (A) -> C {

DanielCardonaRojas

var str = "hhhhh   Hello playground"

extension String {
    static func groupBy(_ string: String, _ f: (Character, Character) -> Bool) -> [String] {
        let array = Array(string) as! [Character]
        let groups = Array.groupBy(array, f)
        return groups.map { g in String(g) }
    }
    
    static func group(_ string: String) -> [String] {

DanielCardonaRojas

class BezierView: UIView {

    private var bezier: UIBezierPath
    
    init(bezier: UIBezierPath) {
        self.bezier = bezier
        let transform = CGAffineTransform()
        transform.scaledBy(x: 2, y: 2)
        let rectBounds = bezier.bounds
        rectBounds.applying(transform)

DanielCardonaRojas

protocol Semigroup {
    /* A semigroup is a set and a binary operator defined for elements within that
       set, to yeild a another element of the same type.
    */
    static func combine (_ lhs: Self, _ rhs: Self) -> Self
}

extension Semigroup {
    // Extending a protocol enables to get free functions based on the implementation of the protocol
    func mappend(_ with: Self) -> Self {