Skip to content

Instantly share code, notes, and snippets.

@royling
royling / 1-sync-vs-async.md
Last active May 3, 2024 06:30
RxJS5: sync vs. async observables

Sync observables created from a synchronous source will emit values synchronously, so the observers will receive values in the order of subscription.

The source iterable is traversed for each observer subscribed. For example, the size of source iterable is M, there are N observers, so the traversal times is M*N. This is explained in RxJS5 Manual:

Plain Observables are unicast (each subscribed Observer owns an independent execution of the Observable)

let sub = Rx.Observable.range(0, 3);

sub.subscribe(value => console.log(`observer 1: ${value}`));
sub.subscribe(value => console.log(`observer 2: ${value}`));
@apolloclark
apolloclark / postgres cheatsheet.md
Last active May 24, 2024 12:25
postgres cheatsheet

Postgres Cheatsheet

This is a collection of the most common commands I run while administering Postgres databases. The variables shown between the open and closed tags, "<" and ">", should be replaced with a name you choose. Postgres has multiple shortcut functions, starting with a forward slash, "". Any SQL command that is not a shortcut, must end with a semicolon, ";". You can use the keyboard UP and DOWN keys to scroll the history of previous commands you've run.

Setup

installation, Ubuntu

http://www.postgresql.org/download/linux/ubuntu/ https://help.ubuntu.com/community/PostgreSQL

@FrancesCoronel
FrancesCoronel / sampleREADME.md
Last active March 26, 2024 01:21
A sample README for all your GitHub projects.

Repository Title Goes Here

Frances Coronel

INSERT GRAPHIC HERE (include hyperlink in image)

Subtitle or Short Description Goes Here

ideally one sentence >

@wpscholar
wpscholar / vagrant-cheat-sheet.md
Last active May 22, 2024 07:14
Vagrant Cheat Sheet

Typing vagrant from the command line will display a list of all available commands.

Be sure that you are in the same directory as the Vagrantfile when running these commands!

Creating a VM

  • vagrant init -- Initialize Vagrant with a Vagrantfile and ./.vagrant directory, using no specified base image. Before you can do vagrant up, you'll need to specify a base image in the Vagrantfile.
  • vagrant init <boxpath> -- Initialize Vagrant with a specific box. To find a box, go to the public Vagrant box catalog. When you find one you like, just replace it's name with boxpath. For example, vagrant init ubuntu/trusty64.

Starting a VM

  • vagrant up -- starts vagrant environment (also provisions only on the FIRST vagrant up)
@brianmacarthur
brianmacarthur / flash-app.js
Last active July 10, 2023 18:41
Flash messaging in Express 4: express-flash vs. custom middleware in ejs, handlebars, or jade
var express = require('express');
var cookieParser = require('cookie-parser');
var session = require('express-session');
var flash = require('express-flash');
var handlebars = require('express-handlebars')
var app = express();
var sessionStore = new session.MemoryStore;
// View Engines
@pongstr
pongstr / shorthand-javascript-techniques.md
Last active June 22, 2022 20:09
Shorthand Coding Techniques. Original post by @samdeering http://www.sitepoint.com/shorthand-javascript-techniques/

Javascript Shorthand Coding Techniques

My (@pongstr) opinion about shorthand coding techniques

Shorthand code is not really a replacement for normal coding but it is very handy and useful in some cases. There are tons of opinions and debates around this but, again it all comes down what is necessary for your codebase and using it responsibly.