Jonathan Chow echojc

Software engineer

echojc / weak_transpose2.scala

Last active December 17, 2015 17:39

	def transpose[T](list: List[List[T]]): List[T] =
	if (list.isEmpty) Nil
	else (list map { _.head }) :::
	transpose(list map { _.tail} filter { !_.isEmpty })

echojc / weak_transpose3.hs

Created May 25, 2013 12:14

	transpose :: [[a]] -> [a]
	transpose [] = []
	transpose input = map head input ++
	transpose (filter (not . null) (map tail input))

echojc / implicit-json-format.scala

Last active August 29, 2015 14:00

Fundep materialiser for spray-json's JsonFormat via superclass implicit (for Scala 2.10.3)

	import scala.language.experimental.macros
	import scala.reflect.macros.Context

	import spray.json._

	trait ImplicitJsonFormat

	object ImplicitJsonFormat {
	implicit def materializeJsonFormat[T]: JsonFormat[T] = macro jfImpl[T]

echojc / conway.scala

Last active August 29, 2015 14:07

Straight to the point implementation of Conway's Game of Life

	object Conway {
	type Cell = (Int, Int)
	type World = Set[Cell]

	def next(w: World): World = w flatMap expand filter alive(w)

	private def expand(c: Cell): Set[Cell] =
	(for (x <- -1 to 1; y <- -1 to 1) yield (c._1 + x, c._2 + y)).toSet

	private def alive(w: World)(c: Cell): Boolean = {

echojc / MapReader.scala

Last active February 26, 2016 05:21

	trait MapReader[T] {
	// should really return Option[T], but let's keep it simple in this example
	def read(map: Map[String, Any], key: String): T
	}

	object MapReader extends MapReaderLowPriorityImplicits {
	// convenience method to retrieve implicit instance explicitly
	def apply[T: MapReader]: MapReader[T] = implicitly[MapReader[T]]

	// these implicits are always implicitly available as long as `MapReader` is in scope

echojc / keybase.md

Created October 5, 2016 21:55

I hereby claim:

I am echojc on github.
I am echojc (https://keybase.io/echojc) on keybase.
I have a public key whose fingerprint is E148 7B9D 3EA0 06A2 CF53 9A81 389D F30E 7772 F372

To claim this, I am signing this object:

echojc / prototyping-area-0.txt

Created November 27, 2016 12:45

Stoked that I hacked together a rudimentary Simon Says game in Shenzhen I/O! http://puu.sh/sw3gW/107bebc92d.png

echojc / vim.html

Created June 18, 2017 09:56

	<!doctype html>
	<html>
	<head>
	<title>vim demo</title>
	<link href="https://cdnjs.cloudflare.com/ajax/libs/normalize/7.0.0/normalize.min.css" rel="stylesheet">
	<link href="https://fonts.googleapis.com/css?family=Source+Code+Pro" rel="stylesheet">
	<style>
	html,
	body {
	height: 100%;

echojc / elevator_saga.js

Created December 2, 2018 03:03

	{
	init: function (elevators, floors) {
	const floor_up_pressed = {};
	const floor_down_pressed = {};

	floors.forEach(floor => {
	const f = floor;
	f.on('up_button_pressed', () => {
	floor_up_pressed[f.floorNum()] = true;
	});

echojc / wt-print.css

Last active April 5, 2019 02:17