teleren/devto huggingface dataset:
Variables and Comments | Shell Scripting 
Tags: linux, devops, tutorial, beginners
Published: 2020-12-01 12:56:25

**This is a multipart blog article series where I am going to explain the concepts of shell scripting and how to write a shell script in Linux, UNIX or Mac based systems. You can also follow this tutorial blog using windows but for that you have to install a bash from.**

_In this article we will see that how can we write comments and different types of variables and how to use them._

1. **Comments:** Comments can be added by using `#` sign, the text written after this sign will be consider as comment.

2. **Variables:**
    - Variables are container which stores some data inside them.
    - There are two types of variable _system variable_ and “user defined variables”.
    - System variables are created and maintained by the LINUX or UNIX system itself. These variables are standard variables defined by the operating system. The standard convention is that they are written in capital case.
    - User defined variables are created and maintained by the user like us. Generally these variables are defined in lower case.
3. **System variables:**
    - **`$BASH`:** This will give you the name of the shell you are using.
    - **`$BASH_VERSION`:** This will give you the version of the bash you are using.
    - **`$HOME`:** This will give the address of home directory.
    - **`$PWD`:** It stands for resent working directory; this will give us the address of present working directory.
    - These are more system variables but these are the most common one.
4. **User defined variables:**
    - We can define a variable in the way `<variable_name>=<value>`. And we can call it like this `echo $<variable_name>`
    - Your variable name should not start with number, becasue shell will not consider it as a varialbe.

_So this was all about variables and comments in shell. Hope you liked it and learned something new from it._

If you have any doubt, question, queries related to this topic or just want to share something with me, then please feel free to contact me.

### 📱 Contact Me

[Twitter](https://twitter.com/r_mishra10),
[LinkedIn](https://www.linkedin.com/in/rahul-mishra-66210b185),
[Telegram](https://t.me/rahul_mishra10),
[Instagram](https://www.instagram.com/rahul_mishra10/?hl=en),

### 📧 Write a mail
<rahulmishra102000@gmail.com>

#### 🚀 Other links

[GitHub](https://github.com/rahulMishra05),
[HackerRank](https://www.hackerrank.com/rahulmishra10201)
What to choose: Ruby or Python?
Tags: ruby, python
Published: 2020-12-01 12:39:32

I asked myself once what determines the popularity of these two languages Ruby and Python? 
Both Ruby and Python have excellent frameworks, open and large communities and are widely spread. It’s no use to tell which one is “better” because they serve different goals. Our team comes to <a href="https://exceed-team.com/tech/ruby-python">a conclusion</a> that Python is an evident choice for developing complex, database driven applications,while Ruby is perfect for startups and quick development.
Progressive Web Apps and the changing face of the mobile web
Tags: programming, coding, development
Published: 2020-12-01 12:30:28

The Internet has come full circle. The evolution of the digital age began with the simple display of information through a single primitive web-page, which progressed into more sophisticated websites and applications for a wide variety of devices. This further transitioned in the last decade in the form of a huge surge in native apps developed for not just the mobile and hand-held tablets but also a slew of tactile movement driven wearables. Progressive Web Apps mark the return of web-based applications in circulation and for good reason too- get the best of both worlds, ie Web and Native app development.

Read more: https://www.terralogic.com/progressive-web-apps-and-the-changing-face-of-the-mobile-web/
Impact of 5G on the eCommerce industry
Tags: ecommerce, 5g, technology
Published: 2020-12-01 12:28:03

E-commerce is possibly the most powerful realm of augmented and virtual reality applications, given that retailers are spending over $ 1 billion a year on the technology.

Today’s consumers are not difficult to go online to shop or use products and services they know. There’s also a lot to say about the rapid rise of mobile commerce. Over time, consumers have become more and more willing to shop on mobile devices, and this trend is driving merchants to provide a powerful, engaging mobile shopping experience.

Not stopping there, mobile devices also play an important role in the journey of shopping at traditional stores. Consumers use the device to research and compare products before buying them in a store.

Read more: https://www.terralogic.com/impact-of-5g-on-ecommerce/
Supporting choiceful (object and array) destructuring in JavaScript and TypeScript
Tags: tutorial, javascript, typescript, functional
Published: 2020-12-01 12:27:13

The joy of object and array destructuring is most likely known to you (check out an example below if it's not 🙂). But what about the joy of being able to choose between them while using the same function? How exciting would that be!?

Wait, but why? Well, because each has its upsides and there is usually no good enough reason to force the developer to use one of them by design. Array destructuring allows you to more succinctly rename the variables but requires remembering the order, while object destructuring forces you to remember the name but doesn't mind the order.

What are object and array destructuring?
```javascript
// object destructuring
const o = {
  firstN: 'Plants',
  v: 'need',
  secondN: 'water'
}
const {firstN, secondN} = o;
console.log(secondN); // water

// array destructuring
const a = ['Plants', 'need', 'water'];
const [firstNoun, verb] = a;
console.log(firstNoun); // Plants
```
They are a succinct way to retrieve variables from a more complex type. Easy to use and easy to read. If used adequately. And in order to maximize the chance that they are indeed used correctly, you might want to defer the choice for which one to use by allowing both when returning from your functions. Just like the [useInView() React Hook](https://github.com/thebuilder/react-intersection-observer) did which inspired me to write this.

First in pure JavaScript:
```javascript
const veryImportantSelfContainedLogic = (n) => {
  const result = ['Plants', 'need', n, 'waters'];

  result.firstWord = result[0];
  result.anotherWord = result[1];
  result.notAWord = result[2];
  result.lastWord = result[3];

  return result;
};
```

And then in TypeScript (highly recommended if you haven't made the transition yet):
```typescript
type VeryImportantSelfContainedLogicResponse = [string, string, number, string] & {
  firstWord: string;
  anotherWord: string;
  notAWord: number;
  lastWord: string;
};

const veryImportantSelfContainedLogic = (
  n: number = 5
): VeryImportantSelfContainedLogicResponse => {
  const result = ['Plants', 'need', n, 'waters'] as VeryImportantSelfContainedLogicResponse;

  result.firstWord = result[0];
  result.anotherWord = result[1];
  result.notAWord = result[2];
  result.lastWord = result[3];

  return result;
};
```

The developer using your function can then choose which type of restructuring to use depending on their mood (or some other considerations if one finds them more important):
```javascript
// decided to rename the second variable in comparison to the function author's intention
const [firstWord, secondWord] = veryImportantSelfContainedLogic(3); 

// has to follow the naming
const {firstWord, anotherWord} = veryImportantSelfContainedLogic(5);

// or redefine it like so
const {firstWord, anotherWord: secondWord} = veryImportantSelfContainedLogic(5);
```

Neat, isn't it? ☀️

Let me know in the comments if you see any downsides in supporting choiceful destructuring by default or if you're all in on the idea 🤓
Printer Spooler Problem | Operating System - M03 P03
Tags: linux, beginners, devops, codenewbie
Published: 2020-12-01 12:18:20

**This is a multipart blog article series, and in this series I am going to explain you the concepts of operating system. This article series is divided into multiple modules and this is the third module which consists of 10 articles.**

_In this article we will discuss about printer spooler problem, and how can we overcome that problem._

### Printer spooler problem
- As we know that printer is a peripheral device, so it is slower in comparison of CPU and memory.
- So, if multiple users send some file to printer to print then **spooler** comes into play.
- Spooler is a program in printer which stores all the files coming to print and when printer is free it gives it to the printer in sequential manner.
 
<!-- Image will come here -->

***This four line code is executed by each process in order to store its file in spooler directory to print.***
```c
Load Ri, m[in]
store SD[Ri], "F-N"
INCR Ri
store m[in], Ri
```
`in: Shared variable`
`m: Memory location`
`Ri: Register`
`F-N: File name`
`SD: Spooler directory`

1. **Line 1:** In line one we are loading free memory location `m[in]`, in register `Ri`
2. **Line 2:** In line two we are storing file name _(F-N)_ in spooler directory _(SD)_ at position `Ri`, which is for instance `0`
3. **Line 3:** In line three we are incrementing the count of `Ri` from `0` to `1`, so next file can be stored in at index `1`
4. **Line 4:** In line four the new file will be stored at incremented memory location `m[in]`

_So this was all about printer spooler problem. Hope you liked it and learned something new from it._

If you have any doubt, question, queries related to this topic or just want to share something with me, then please feel free to contact me.

### 📱 Contact Me

[Twitter](https://twitter.com/r_mishra10)
[LinkedIn](https://www.linkedin.com/in/rahul-mishra-66210b185)
[Telegram](https://t.me/rahul_mishra10)
[Instagram](https://www.instagram.com/rahul_mishra10/?hl=en)

### 📧 Write a mail
<rahulmishra102000@gmail.com>

#### 🚀 Other links

[GitHub](https://github.com/rahulMishra05)
[HackerRank](https://www.hackerrank.com/rahulmishra10201)
Example SSG website performance results
Tags: gatsby, webdev, performance, hugo
Published: 2020-12-01 12:14:43

A couple of weeks ago we (Bejamas) published [beginners guide to static site generators](https://bejamas.io/blog/static-site-generators/). A comprehensive overview of the top, most popular SSGs on the market. For each one, we’ve covered its history and state of the project at the moment. The best features and strengths. Ecosystem and most popular websites built with SSG in question. And finally how to start a basic project and deploy it.

With speed and performance being one of the key selling points for jamstack I was, as usual, interested in the performance scores of those websites we chose to showcase for each of the SSGs mentioned in the post. The results:
![Alt Text](https://dev-to-uploads.s3.amazonaws.com/i/isexte7lkdqxa06xj4zr.jpg)
As you can see Eleventy, followed by Bridgetown, on average, has the best results. But the thing is, and I can't emphasize this enough, it really depends on each use case ie the complexity of the website in question.

Still, SSG space looks promising :-) 

What would be your takeaway from this? Would love to get some feedback. Let's discuss it in the comment section below👇
Learning how to teach myself to code
Tags: tutorial, learning, help, devjournal
Published: 2020-12-01 11:58:43

4 years ago I started learning how to code, and it was _really_ difficult! It's still difficult, but I now have a collection of tools and perspectives that make it less daunting (more on that below). Leveling up requires one more abstraction to wrap my head around, or one more API to understand. I can do it. 

But I don't think it needed to be so difficult, so now I'm building [Code School Meta](https://codeschoolmeta.com) to make it easier to teach yourself how to code. 

Learning to code has been fun, ultimately successful, and life changing (hello job security!) but at the beginning it was sooo slow, and super tricky.

I remember feeling like an imposter, and thinking that I was definitely not a real developer - I hadn't taken any classes in computer science. I knew almost nothing about anything. 

The process began with Pandas, a (_the_) Python analytics library. Spreadsheets were slowing me down at work, and I was bored. I found this [great tutorial](https://youtu.be/5JnMutdy6Fw) by Brandon Rhodes. From there I found out about Jupyter Notebooks, and then I found about Github pages and how to make a blog using [pelican](https://blog.getpelican.com/). 

That led to HTML and CSS (and also JavaScript, which I tried very hard to avoid for as long as possible). I felt like a monkey bashing a keyboard as I tried to make HTML elements do what I wanted.

Git was next, but I found this [amazing tutorial](https://blog.johnmathews.eu/rys-git-tutorial.html) to help me learn. It made Git seem OK, and also helped HTML and CSS make more sense too. Bonus! 

I suddenly realized that great learning materials are crucial if I'm to keep momentum and enjoy learning. 

So now I'm now working on [Code School: Meta](https://codeschoolmeta.com). It's an online community to make it easier to teach yourself how to code - less confusion, more encouragement, lots of high quality resources. 

If you'd like to know more, please [check it out](https://codeschoolmeta.com) and sign up for updates.
JavaScript Code Daily Challenge #10
Tags: javascript, challenge, codenewbie, beginners
Published: 2020-12-01 11:57:40

# **About**

This is a series of JavaScript Code Daily Challenge. Each day I show a few solutions written in JavaScript. The questions are from coding practice/contest sites such as HackerRank, LeetCode, Codeforces, Atcoder and etc.

> Number Line Jumps
> [https://www.hackerrank.com/challenges/kangaroo](https://www.hackerrank.com/challenges/kangaroo)

```javascript
'use strict';

const fs = require('fs');

process.stdin.resume();
process.stdin.setEncoding('utf-8');

let inputString = '';
let currentLine = 0;

process.stdin.on('data', inputStdin => {
    inputString += inputStdin;
});

process.stdin.on('end', _ => {
    inputString = inputString.replace(/\s*$/, '')
        .split('\n')
        .map(str => str.replace(/\s*$/, ''));

    main();
});

function readLine() {
    return inputString[currentLine++];
}
```
> Complete the kangaroo function in comment.

```javascript
function kangaroo(x1, v1, x2, v2) {

}
```
```javascript
function main() {
    const ws = fs.createWriteStream(process.env.OUTPUT_PATH);

    const x1V1X2V2 = readLine().split(' ');

    const x1 = parseInt(x1V1X2V2[0], 10);

    const v1 = parseInt(x1V1X2V2[1], 10);

    const x2 = parseInt(x1V1X2V2[2], 10);

    const v2 = parseInt(x1V1X2V2[3], 10);

    let result = kangaroo(x1, v1, x2, v2);

    ws.write(result + "\n");

    ws.end();
}
```
Top Industry Sectors that can Make the Most of On-demand Delivery Apps
Tags: android, discuss, devjournal
Published: 2020-12-01 11:55:54

We live in a technology-driven world and rely heavily on mobile apps for accomplishing our daily tasks. On-demand delivery apps have completely changed the way we live by adding more comfort and convenience. This is a reason why such apps have gained a lot of popularity worldwide.

Think of Uber, Instacart, and Airbnb- all these applications have made their strong presence in thousands of millions of smartphones worldwide. Their success stories have become an inspiration for many startups that want to leverage the benefits of a booming on-demand economy. It is fair to mention that on-demand apps play a vital role in setting new trends in the domain of mobile app development every year.

Be it beauty or healthcare, car rentals or home service, bakery, or food delivery, every service industry can make the most of a thriving on-demand app development domain. What’s more, this list keeps on increasing as time advances in line with the changing requirements of people.

Let’s make a list of service industries that have leveraged the benefits of on-demand app development services.

Food Delivery Service- In this pandemic time, on-demand food delivery app and on-demand grocery delivery apps top the chart of the most downloaded apps. People prefer to place orders for their favorite foods and groceries using apps and get them delivered at their doorsteps without going out. This comfort and convenience have made on-demand food delivery apps in demand.

Many restaurants or takeaways have launched their apps for offering on-demand food delivery services to their customers. These apps not only help them attract more customers but also enable them to streamline ordering and delivery processes.
node.js start
Published: 2020-12-01 11:53:36

I bought the course to create web application by node.js and express (mejor application framework on node.js) course on Udemy.

*Udemy had a discount sale called cyber friday.

I started Node.js udemy course.
I installed Visual Studio Code.
* I had installed node.js yet. Because I had tried to create some web application for me. But I don't know how I can create it on node.js. So, I bought node.js and express course on udemy and started to learn it.
My goal is to create the typing application for me.
TOP 7 Pro Tips For Web DEvelopers !!!
Tags: javascript, css, html, react
Published: 2020-12-01 11:43:27

I Have Been Creating Many Repos ...

Every Web Developer must have a basic understanding of HTML, CSS, and JavaScript.

Responsive Web Design is used in all types of modern web development.

1: 
Pick a Text Editor 
VS Code is the is the top choice for web developers, which makes it a great place to start — it’s personally what I use. It is free and open source, with tons of plugins to make you more productive. However, there are many excellent options available such as Atom, WebStorm, or Vim (for the hardcore).

2: 
Only focus on a few skills: Ex. JavaScript, React, Node. Don’t try to learn everything — React, Vue, Angular, jQuery, Backbone, etc. Get as good as you can learning the minimal required languages/libraries. Go deep, not wide.

3:
Build a portfolio website and use the portfolio API to power the data. The ability to show you can build applications is essential to hiring managers.

4:
Apply to as many jobs as you can as long as they fit your skillset. Don’t give up! You will eventually find your role if you keep working. It’s a long and hard road, but well worth the effort if you are passionate about the field.

5:
Practice for the interview. Use “Cracking the Coding Interview” and websites to become comfortable with answering interview questions.

6:
Read the “You Don’t Know JavaScript” series. This will ensure you know the language inside and out.

7:
Keep building projects — projects are the best way to learn and show that you understand how to build apps for the real world.

Keep GOING Guys!!!
Software Developer or Software Artist?
Published: 2020-12-01 11:38:27

I was an artist in the conventional sense. I have spent the last 7 years creating conceptual art pieces were the outcomes have been traditional art objects; photographs, cyanotypes, video installations and sculpture. Sure, I was pushing convention within my practice of photography by presenting an outcome as a plaster sculpture, but I was really only deviating in my result.

More recently I have started to deviate in my process. Trading the click of a camera shutter for the clattering of keys on a keyboard. Swapping the photographic studio and all of its tripods, lights and black out curtains for a computer screen, a digital workspace, one environment that hosts all of its tools and equipment digitally. 

At first I felt out of my depth. Art is accessible because we don’t need instructions on how to access and use its materials. It is tacit. It is freeing. 

Programming felt so inaccessible. The idea of having to learn a new language before you could even start felt terrifying.
Then I realised the programming language exists so that it is accessible. One system that transcends language and culture and is accessible to everyone. 

### Isn’t it restrictive?
When I was in the tutorial phase of my journey, I couldn’t help but think, boy this is restrictive! I thought maybe it was because I was from an art background and was lucky to not have to adhere to many rules, but mostly, I thought it was because it was all of an artist’s trigger words;

- Computers
- Science
- Math

As it turns out, it is freeing. 
Its potential is infinite and once you learn the language and syntax you can create anything.
There is beauty and creativity in every aspect, in thinking of a concept, in the process of writing it, in the creative problem solving and clean-up of the code, and undeniably, in the outcome.

In many ways it is even less restrictive than art; the community embraces collaboration and shares code dispelling most problems about authorship and originality. It is totally scalable, it can be live, interactive or pre-made, it can be different every time it is ran, it can be imitative or abstract, it can be responsive to embedded information or live features and it can display 16,777,216 colours.  How can something so malleable be restrictive? 
There is freedom in navigating the structures of a system. 

### "But the programmer isn’t a real artist because they don’t have real creative freedom!"
I could not disagree more. Every piece of code totally reflects the author of it, much like a novel does. The programmer’s code is absolutely a declaration of themselves.  
Also, much like a novel, it does not need to be shared, seen, or experienced in order for it to achieve the status of art. It is art because it is art. Art is about executing a concept out of the materiality of your practice, but overall it is about creating. 

**That’s why computer programmers are artists.**
Panel Discussion: Data for Good [Create: Data]
Tags: news, datascience, azure
Published: 2020-12-01 11:21:56

Panel: Data for Good

# Update!
Few, what an experience, alright.
Want to catch up with the panel session? You can watch it on demand -> [here](https://channel9.msdn.com/Events/MS-Create/Data/Panel-Data-for-Good?WT.mc_id=data-11733-adpolak).

For watching more sessions from Create: Data on-demand, click [here](https://channel9.msdn.com/Events/MS-Create/Data?WT.mc_id=data-11733-adpolak).

-------------------



 
Provably one of the most exciting topics of the year for everyone who works with data. How can we leverage data to do good for our communities and improve people's lives?

![](https://media.giphy.com/media/qEA9njXuIMz6w01GaC/giphy.gif)

Join four inspiring and accomplished leaders in the data space for this Data For Good panel. They share their perspectives about what good data is and how it relates to actually doing good. Take away learnings on how data tools can help us in keeping our data healthy.

---------------------


Register now for [free](https://aka.ms/createdata ); please share your questions, ideas, and thoughts in the comment section. I'm happy to bring it with the panel experts to make sure all your questions are answered!