Skip to main content

Welcome to Javascript

Node.js is an open source environment for Javascript.

And now that I've concluded the basics with Python, let's keep the ball rolling. I find that, even though Javascript looks a lot more complicated, I gel with it a bit easier, and I'm not sure why.

This is around the first 35 minutes of this tutorial here. I'm going to work through this and find some other resources. I've already found said resources and they look a little different in the code department than this, but it's mostly the same.

We make three things here;



  • Introduce ourselves
  • Make a small game
  • Establish classes and events





A node module is a javascript file.

My initial is appin.js, tutorial file is tut.js. You may want to open and follow along!

Javascript Separates your commands in a way instead of shoving them all into one file by calling to other files that are in the same path (./) and using const tut = require(‘./tut’)



I export classes and PI; It looks a bit ugly like this.

module.exports.PI = PI;
module.exports.Mathing = Mathing;

But we can also do it like this;

module.exports = {sum : sum, PI : PI, Mathing : Mathing}

Events module and events emitter

Event Emitters are what happens when an action - passing a control - takes place

Person is a class, and we put Mori and Hanlon in that class as two seperate objects. I modify the introduction for each name.

let Mori = new Person('Mori');
//Person extends eventemitter class
// Mori is an instance of the event emitter class
Mori.on('name',()=>{
console.log('Name is ' + Mori.name);
})
let Hanlon = new Person('Hanlon');
//Person extends eventemitter class
// Hanlon is an instance of the event emitter class
Hanlon.on('name',()=>{
console.log('And I am ' + Hanlon.name);


Finally, our little game. Variables num3 and num4 (I used num1 and num2 in tut.js, which appin.js pulled) are assigned a random number between 1 and 10 to add.

Q: How can we make the modifier random also?

else{
rl.setPrompt('No try again\n');
//the little new line bugger tripped me up
rl.prompt();
rl.on('line',(userInput)=>{ //this input will be tested
if(userInput.trim() == answer)
rl.close();
else {
rl.setPrompt(`${ userInput } is wrong \n
Try again. You can do it!\n`)
rl.prompt();
}
//it's a loop
})

Line 81 (See GitHub) says "This user input will be tested", so that random strings aren't seen as correct as opposed to the right answer.

If the user gets the question wrong, it loops until they get it correct ('answer'), then it stops the program, returning to the prompt.



Comments

Popular posts from this blog

Connecting IoT Devices to a Registration Server (Packet Tracer, Cisco)

In Packet Tracer, a demo software made by Cisco Systems. It certainly has changed a lot since 2016. It's almost an Olympic feat to even get started with it now, but it does look snazzy. This is for the new CCNA, that integrates, among other things, IoT and Automation, which I've worked on here before. Instructions here . I don't know if this is an aspect of "Let's make sure people are paying attention and not simply following blindly", or an oversight - The instructions indicate a Meraki Server, when a regular one is the working option here. I have to enable the IoT service on this server. Also, we assign the server an IPv4 address from a DHCP pool instead of giving it a static one. For something that handles our IoT business, perhaps that's safer; Getting a new IPv4 address every week or so is a minimal step against an intruder, but it is a step. There are no devices associated with this new server; In an earlier lab (not shown), I attached them to 'H

What Do You Need? [List of Offered Services]

2023 Version is here, at this handy Notion Page.

Building, Breaking, and Building A CRM with Retool

 I like no- or low-code solutions to things. I've often wanted to simply push a button or move some GUI around and have the code implement itself.  I've thought about building something that's like a customer relationship management (CRM) system for keeping up with my network better than my little spreadsheet where I click links and then go like something. The general idea in this CRM Development is:  To have a GUI to add people to a NRM (Network Relationship Management).       Attach it to a database (MySQL is what I went with eventually using Amazon Relational Database service, but you can use PostGRES, and probably others).     Make sure components are connected to each other in the retool interface. This video is a good start. Watching the tutorial video, heard some SQL commands and went 'Oh no 😳" before going "Wait I know basic SQL", which is good, because you'll see.  When you get set up, there's a plethora of resources you can use -- Incl