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JavaScript function hoisting by example

Below are many examples of function hoisting behavior in JavaScript. Ones marked as works successfuly print 'hi!' without errors.

To play around with these examples (recommended) clone them with git and execute them with e.g. node a.js

Notes on hoisting

(I may be using incorrect terms below, please forgive me)

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// To run this file: node index.js
// Then in your browser: http://localhost:8080
var http = require('http');

var port = 8080;

var server = http.createServer();

// Start the HTTP server, start listening for requests
server.listen(port, function(error) {

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function signup (email, password) {
  const salt = uuid();
  const hashedPassword = hash(`${salt}${password}`);
  // this stores everything in the DB
  createUser(email, salt, hashedPassword);
}

function login (request, response) {
  // get the salt - SELECT salt FROM users 
  // WHERE email = ?, [email]

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function archetype (request, response) {
  // Get Data out of the request

  // Process that data

  // Build and send the response
  response.setHeaders();
  response.write();
  response.end();
}

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CREATE TABLE userType (
	id int NOT NULL,
  description varchar(255) NOT NULL,
  PRIMARY KEY (`id`)
);

CREATE TABLE user (
	id char(32) NOT NULL, -- use uuid() on INSERT
  username varchar(24) NOT NULL,  -- rob
  passwordHash char(40) NOT NULL, -- c8fed00eb2e87f1cee8e90ebbe870c190ac3848c

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CREATE VIEW ClassesAndRunningInformation AS
SELECT 
  ClassGroup.Name AS ClassGroupName,
  Running.StartDate,
  Module.Name AS ModuleName,
  Module.Length AS ModuleLength
FROM
  ClassGroup
    INNER JOIN
  Running

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function Observable(init_value) {
    var _value = init_value;
    var subscriber = [];

    function obs() {
        if (arguments.length) {
            _value = arguments[0];
            obs.trigger();
            return this;
        } else {

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class Observable {

  constructor(subscriber) {
    this.subscriber = subscriber
  }

  subscribe(observer) {
    if (typeof observer == 'function') observer = {next: observer}
    if (!observer.next)     observer.next     = () => {}
    if (!observer.complete) observer.complete = () => {}

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##Setup your server (this would ideally be done with automated provisioning)

• add a deploy user with password-less ssh see this gist
• install forever npm install -g forever

##Install flightplan

• npm install -g flightplan
• in your project folder npm install flightplan --save-dev
• create a flightplan.js file

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PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h):

• -E: will describe the underlaying queries of the \ commands (cool for learning!)
• -l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)