boraseoksoon

(defn merge-maps [& maps]
  ;; (sanitize-map)
  (if (every? map? maps)
    (apply merge-with merge-maps maps)
    (last maps)))

(defn sanitize-map [m]
  (if (map? m)
    (let [clean-val (fn [[k v]]
                      (let [v' (sanitize-map v)]

boraseoksoon

import Foundation

// today coding: write a reversed value semantic enum list.

indirect enum List<T> {
    case empty
    case node(T, List<T>)
}

extension List {

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indirect enum List<T> {
    case empty
    case node(T, List<T>)
    
    var value: T? {
        if case .node(let value, _) = self {
            return value
        } else {
            return nil
        }

boraseoksoon

import Foundation

// today coding: implement map filter reduce of the value semantic enum list.

indirect enum List<T> {
    case empty
    case node(T, List<T>)
}

extension List {

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import SwiftUI

// today coding: async sequence in Swift

struct URLSequence: AsyncSequence {
    typealias AsyncIterator = URLIterator
    typealias Element = Data
    
    let urls: [URL]
    

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import Foundation

// daily coding 2022/05/06

// seven ways to solve fibonnaci in Swift.

// (0) imperative style
// (1) using any sequence and iterator
// (2) normal recursion version
// (3) shorter recursion version

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let res4 = Array(
    AnySequence { () -> AnyIterator<Int> in
        var t1 = (0, 1)
        return AnyIterator<Int> {
            let (a, b) = t1
            t1 = (b, a + b)
            return b
        }
    }
    .prefix(10)

boraseoksoon

import Foundation

struct Recursion {
    
    /// Generate `a growing closure` to keep track of the all of history of task, and
    /// run a function as a given parameter after executing all of previous tasks if tasks exist, and add the function to the tasks.
    /// - Returns: `the growing closure` to remember the tasks to execute.
    ///
    /// ```
    /// let recur = Recursion.generateGrowingClosure()

boraseoksoon

import Foundation

struct Recursion {
    static func generated()
        -> ((() -> Void)?) -> ()
    {
        var tasks: [(() -> ())?] = []
        
        let closure = { (task: (() -> Void)?) in
            tasks.append(task)

boraseoksoon

import Foundation

struct Recursion {
    static func recur(task baseTask: @escaping () -> Void,
                      willGrow: Bool = true)
        -> (( () -> Void)?) -> Void
    {
        var next = 0
        
        return { lastTask in