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Nick Taylor
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September 9th, 2021: What did you learn this week?

It's that time of the week again. So wonderful devs, what did you learn this week? It could be programming tips, career advice etc.

![A picture it a dog waving their paw with the caption “Learning, cool at school or at home”](https://media.giphy.com/media/1xpm1nTQiRL96Di3Q6/giphy.gif)

Feel free to comment with what you learnt and/or reference your TIL post to give it some more exposure.

#todayilearned

Summarize a concept that is new to you.

And remember, if something you learnt was a big win for you, then you know where to drop it as well.👇👇🏻👇🏼👇🏽👇🏾👇🏿

![Drama from Entourage screaming “Victory!”](https://media.giphy.com/media/lnlAifQdenMxW/giphy.gif)

Top comments (29)

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vonheikemen profile image
Heiker • Edited

I learned about envsubst. I wish I knew about this before. This utility can substitute environment variables in a string that come from stdin.

I don't have many use cases for this but I think it would be very useful in config files that I share across multiple machines.

Quick example. Somewhere in a github repo I have a file called .npmrc, which I copy to any new machine I get. Inside that file I have this.

prefix=/absolute/path/to/npm/packages
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I don't like it, I want to replace that absolute path with this.

prefix=$XDG_CONFIG_HOME/npm/packages
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So, what I can do is create a template file and then create .npmrc from that.

envsubst < ~/templates/npmrc > ~/.npmrc
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The result on linux should be this:

prefix=/home/user/.config/npm/packages
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And if I wanted, I think I could use curl to fetch the content of the file and then pipe it to envsubst. So technically I don't even need the template in my filesystem.

EDIT: Yes, curl works like a charm.

curl -s "https://raw.githubusercontent.com/<my-user>/<some-repo>/main/npmrc" \
  | envsubst > ~/.npmrc
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nickytonline profile image
Nick Taylor

Nice!

A kangaroo playing an electric guitar

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rubix982 profile image
Saif Islam • Edited

This week, I had,

  • A few things at home to windup and get fixed

  • Started University again, 7th semester. Learning about the .NET Framework, Information & CyberSecurity, Professional Practies & Ethics In IT, and finally, I have a my first class tomorrow for "Design, Defects & Restructuring"

  • I had some free time this week ... so I started working towards a quick specialization, "Computer Security and Systems Management Specialization", coursera.org/specializations/compu.... I've just started the 2nd out of 4 courses from the specialization.

  • Podcast habit. I've been continuously listening to podcasts whenever I can. I think I've listened to about 4-5 sessions already - and I'm really excited to listen to more

  • Managed sleep schedule - I count this as an achievement with my ongoing Uni

  • Spent quality time with friends - for me, this is very essential. Life behind a screen can sometimes become boring

  • Choose Open Source projects that I'll be contributing to over till next year starts. Yay!

  • Just published an article on dev.to! dev.to/rubix982/a-brief-discussion...

  • Will be staying in touch with the Jenkins team on Slack to contribute to the "Jenkins Summit - DevOps World"! Woohoo!

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nickytonline profile image
Nick Taylor

Yeah!

A T-Rex saying Yeah!

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rubix982 profile image
Saif Islam

:D

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jonathanyeong profile image
Jonathan Yeong

Learning about Character Encoding for strings! Here's a snippet from my permanent note:

Every character that we see is represented as a number on the computer. To be specific, it's a series of bits. But this process of transforming a visual character into a number is done through character encoding. Character encoding is a map for the computer to transform this number into the character we see. It's a cipher, a key, to crack the code.

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nickytonline profile image
Nick Taylor

Shia LeBoeuf in character saying Magic!

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behnoodeghbali profile image
Behnood Eghbali • Edited

I learned how to fetch URLs and how to write HTTP web services in Go. Here's an interesting talk by Mat Ryer about writing HTTP web services at GopherCon 2019: youtube.com/watch?v=rWBSMsLG8po

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nickytonline profile image
Nick Taylor

Noice!

Noice!

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piratax007 profile image
Fausto Mauricio Lagos Suárez • Edited

I learned about assert statements and decorators. The first one is such a tool to debug your code and the second one is a way to modify an object, function or method without altering his code. Decorators are a wonderful way to reuse code adding functionalities.

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Nick Taylor

Actor Leonardo DiCaprio as Gatsby doing a cheers

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seankimdev profile image
Sean Kim

I learned to use Material UI. A quick and simple way to style a React app.
It took some time getting used to its setup, but definitely worth it. The tutorial video below by The Net Ninja helped a lot.

m.youtube.com/playlist?list=PL4cUx...

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nickytonline profile image
Nick Taylor

Hot Rod saying Cool beans!

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nyarehd profile image
Nyareh David • Edited

Not related to coding but I've learnt very valuable lesson that kept wasting my time for months.
Linux.
I thought linux might be better for programming than window so I tried to switch to linux full time.It was a disaster. I needed to spend many hours troubleshooting things that didn't exist on window.
Now, I have accepted and learned that coding on window is OK.

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peter279k

I learn how to use the Firebase and Google Cloud Function to deploy my web crawler and let my web crawler be a API service on the FaaS computing :).

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Nick Taylor

Awesome!

Hackerman from Kung Fury putting on a Nintendo Power glove

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Eddy Vinck

I learned how much work it really is to launch a product. I also learned how addictive it is to get Gumroad sales notifications while sleeping or working my job 😆

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Nick Taylor

A crab dancing

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vaibhavkhulbe profile image
Vaibhav Khulbe

Just started with TypeScript! I am doing it all with its docs. It's well written and easy to consume if you have a good JS knowledge :)

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Nick Taylor

Nice!

Nice