Pure Functions / Intro to JavaScript ES6 programming, lesson 17

Explore the idea of determinism, side effects, and purity in functions. Get to know the beauty of pure functions.

[JackCkiller]

bra this is some really original shit. really good content

[lostofis]

Amazing explanation, this is the best explanation I ever seen about Pure Function. I'm illuminated!

[ssj]

Wtf, I just found this channel, the explanations are just incredible, i'm terribly sad they have stopped tbh

[JayRGabz]

this video deserves more views.... and this channel deserves more subscribers

[cyberlord]

Beautiful presentation. Educational videos here on youtube vary from ones which require effort to understand and those like yours which feels like you are downloading knowledge directly into your brain. The language-agnostic approach of your presentation was also very helpful for those of us who want to understand this concept but do not work with javascript. Great job!

[faizahmadfaiz]

Very useful! The way of explaining was so clear .How you relate and give the overall picture was awesome!

[LeeDazler]

you do the best videos to explain javascript, thaink you!

[ibknl]

The best explanation of Pure function I have gone through online till now. This is the first video of your channel I watched and I just immediately subscribed. 👍

[fadyahjoudah]

kudos for the effort, flowless delivery

[hh]

wow very good visual explanation, difficult to forget !, thanks

[EastSun]

This is freaking AWESOME ✨🔥🚀! Please keep updating, thank you!

[kalsho]

we should invent a term of PURE TUTORIAL.. I'm surprised why you stop producing this type of AMAZING work !!

[aashishsapkota]

Excellent explanation, the examples provided were mind-blowing you guys must be very intuitively knowledgeable about defining in that way. I loved it keep it up, really helping us.

[raconvid]

I love how he does the irl box functions

[CyrusPieris]

I really enjoyed this series. Hope you will continue. I am going to watch it again 😀

[dawid_dahl]

Really love these videos. Hope you’ll make more!

[JackCkiller]

plus the notes on your lessons are really useful

[dEsTiNyHaCkEr]

this is some next-level video, just wow!

[ishwarrimal]

And I bet u.. I was destined to watch this video today. :D

[AhmedIsam]

Couple of things to add:
In functional programming paradigm:
1- Even the argument itself that is sent to a function MUST NOT be changed, this is thought of as an evil behaviour. For example, if a matrix is sent to a function, the function is not allowed to manipulate its entries. It can only copy it and manipulate the entries of a copy (could be expensive).
This is so crucial, that in Julia programming, they stipulate that a function should have a bang "!" in its name as a grim reminder to the user that this function has evil behaviour.
2- A MASSIVE consequence of this style is: Object Oriented Programming is bullshit. That's simply because methods of class have access to data of the class (self). In fact, the quintessence of OOP (combining data and code) is antethical to the spirit of functional programming that says a function is a function, it is separate from data.

Just like Dynamic Programming is flexible and feels awesome for a beginner and fails miserably in large projects, OOP to FP is similar. Once your code is in order of tens of thousands of lines, you can't track what's going on and you start to appreciate functional programming.