DLakomy

The introduction to Reactive Programming you've been missing

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

	killall Xcode
	xcrun -k
	xcodebuild -alltargets clean
	rm -rf "$(getconf DARWIN_USER_CACHE_DIR)/org.llvm.clang/ModuleCache"
	rm -rf "$(getconf DARWIN_USER_CACHE_DIR)/org.llvm.clang.$(whoami)/ModuleCache"
	rm -rf /Applications/Xcode.app
	rm -rf ~/Library/Caches/com.apple.dt.Xcode
	rm -rf ~/Library/Developer
	rm -rf ~/Library/MobileDevice
	rm -rf ~/Library/Preferences/com.apple.dt.Xcode.plist

	package com.example

	import java.text.NumberFormat
	import java.time.Instant

	import cats.effect.{IO, Sync, Timer}
	import fs2.{Chunk, Stream}
	import monix.eval.Task
	import monix.execution.Scheduler
	import monix.reactive.Observable


	import cats.Monad
	import cats.effect.concurrent.{Ref, Semaphore}
	import cats.effect.{Concurrent, Resource}
	import cats.implicits._
	import fs2.{Pipe, Stream}
	import fs2.concurrent.{NoneTerminatedQueue, Queue}

	/** Represents the ability to enqueue keyed items into a stream of queues that emits homogenous keyed streams.
	*

	val n = 9
	val s = Math.sqrt(n).toInt
	type Board = IndexedSeq[IndexedSeq[Int]]

	def solve(board: Board, cell: Int = 0): Option[Board] = (cell%n, cell/n) match {
	case (r, `n`) => Some(board)
	case (r, c) if board(r)(c) > 0 => solve(board, cell + 1)
	case (r, c) =>
	def guess(x: Int) = solve(board.updated(r, board(r).updated(c, x)), cell + 1)
	val used = board.indices.flatMap(i => Seq(board(r)(i), board(i)(c), board(s(r/s) + i/s)(s(c/s) + i%s)))

	/*
	* Code contributed to Rosetta Code: <http://rosettacode.org/wiki/Tic-tac-toe#Scala>
	*
	* Creative commons license "CC0 1.0 Universal (CC0 1.0)"
	* <http://creativecommons.org/publicdomain/zero/1.0/>
	* To the extent possible under law, Rubén Béjar <http://www.rubenbejar.com>
	* has waived all copyright and related or neighboring rights to this
	* source file. This work is published from: Spain.
	*
	* Computers vs. human. Human starts.