Sova sergeysova

Rust/Haskell: Higher-Kinded Types (HKT)

A higher kinded type is a concept that reifies a type constructor as an actual type.

A type constructor can be thought of in these analogies:

like a function in the type universe
as a type with a "hole" in it

Project Title

One Paragraph of project description goes here

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See deployment for notes on how to deploy the project on a live system.

Prerequisites

@kangax's ES6 quiz, explained

@kangax created a new interesting quiz, this time devoted to ES6 (aka ES2015). I found this quiz very interesting and quite hard (made myself 3 mistakes on first pass).

Here we go with the explanations:

Question 1:

(function(x, f = () =&gt; x) {

Update: https://www.cyanhall.com/posts/notes/7.homebrew-cheatsheet/#java

on El Capitan, after installing the brew...

$ brew update
$ brew tap caskroom/cask
$ brew install Caskroom/cask/java

And Java 8 will be installed at /Library/Java/JavaVirtualMachines/jdk1.8.xxx.jdk/

Docker - How to cleanup (unused) resources

Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...

delete volumes

// see: https://github.com/chadoe/docker-cleanup-volumes

$ docker volume rm $(docker volume ls -qf dangling=true)

$ docker volume ls -qf dangling=true | xargs -r docker volume rm

Debugging ES6 in VS Code

My current editor of choice for all things related to Javascript and Node is VS Code, which I highly recommend. The other day I needed to hunt down a bug in one of my tests written in ES6, which at time of writing is not fully supported in Node. Shortly after, I found myself down the rabbit hole of debugging in VS Code and realized this isn't as straightforward as I thought initially. This short post summarizes the steps I took to make debugging ES6 in VS Code frictionless.

What doesn't work

My first approach was a launch configuration in launch.json mimicking tape -r babel-register ./path/to/testfile.js with babel configured to create inline sourcemaps in my package.json. The debugging started but breakpoints and stepping through the code in VS Code were a complete mess. Apparently, ad-hoc transpilation via babel-require-hook and inline sourcemaps do not work in VS Code. The same result for attaching (instead of launch) to `babel-node

	CREATE OR REPLACE FUNCTION table_update_notify() RETURNS trigger AS $$
	DECLARE
	id bigint;
	BEGIN
	IF TG_OP = 'INSERT' OR TG_OP = 'UPDATE' THEN
	id = NEW.id;
	ELSE
	id = OLD.id;
	END IF;
	PERFORM pg_notify('table_update', json_build_object('table', TG_TABLE_NAME, 'id', id, 'type', TG_OP)::text);

	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8"/>
	<title>array: .native vs .forEach vs .map #jsbench #jsperf</title>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/benchmark/1.0.0/benchmark.min.js"></script>
	<script src="./suite.js"></script>
	</head>
	<body>
	<h1>Open the console to view the results</h1>

	// This is free and unencumbered software released into the public domain.

	// Marshals a string to an Uint8Array.
	function encodeUTF8(s) {
	var i = 0, bytes = new Uint8Array(s.length * 4);
	for (var ci = 0; ci != s.length; ci++) {
	var c = s.charCodeAt(ci);
	if (c < 128) {
	bytes[i++] = c;
	continue;

	0 22 * * 1,2,3,4,5 /path/to/git_changes.sh /path/to/projects/ # Sends 5 PM EST if server time is UTC
	0 21 * * 5 /path/to/git_changes.sh -w /path/to/projects # Sends Friday @ 4PM EST if server time is UTC