Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Learning Functional Programming with JavaScript
Search
Anjana Sofia Vakil
April 24, 2016
Programming
0
830
Learning Functional Programming with JavaScript
Given at JSUnconf 2016 (
http://2016.jsunconf.eu/
)
Anjana Sofia Vakil
April 24, 2016
Tweet
Share
More Decks by Anjana Sofia Vakil
See All by Anjana Sofia Vakil
The Art of Functional Programming
vakila
0
200
First Steps into Functional Programming
vakila
7
2.4k
The Language of Programming
vakila
4
590
Recursion, Iteration, & JavaScript: A love story
vakila
1
430
From Big Band Web App to Serverless Bebop
vakila
0
500
Embracing Constraints
vakila
1
200
Programming across paradigms
vakila
1
720
Immutable data structures for functional JavaScript
vakila
7
1.7k
Functional Programming: What? Why? How?
vakila
1
280
Other Decks in Programming
See All in Programming
Dart 参戦!!静的型付き言語界の隠れた実力者
kno3a87
0
160
変化を楽しむエンジニアリング ~ いままでとこれから ~
murajun1978
0
670
バイブコーディング超えてバイブデプロイ〜CloudflareMCPで実現する、未来のアプリケーションデリバリー〜
azukiazusa1
3
780
Go製CLIツールをnpmで配布するには
syumai
2
1.1k
商品比較サービス「マイベスト」における パーソナライズレコメンドの第一歩
ucchiii43
0
270
CEDEC 2025 『ゲームにおけるリアルタイム通信への QUIC導入事例の紹介』
segadevtech
2
750
新世界の理解
koriym
0
130
Scale out your Claude Code ~自社専用Agentで10xする開発プロセス~
yukukotani
5
970
GUI操作LLMの最新動向: UI-TARSと関連論文紹介
kfujikawa
0
430
Streamlitで実現できるようになったこと、実現してくれたこと
ayumu_yamaguchi
2
270
Quality Gates in the Age of Agentic Coding
helmedeiros
PRO
1
120
DataformでPythonする / dataform-de-python
snhryt
0
150
Featured
See All Featured
How to Ace a Technical Interview
jacobian
278
23k
CSS Pre-Processors: Stylus, Less & Sass
bermonpainter
357
30k
Rebuilding a faster, lazier Slack
samanthasiow
83
9.1k
Designing Dashboards & Data Visualisations in Web Apps
destraynor
231
53k
Visualization
eitanlees
146
16k
Faster Mobile Websites
deanohume
308
31k
Raft: Consensus for Rubyists
vanstee
140
7k
Why Our Code Smells
bkeepers
PRO
337
57k
ReactJS: Keep Simple. Everything can be a component!
pedronauck
667
120k
"I'm Feeling Lucky" - Building Great Search Experiences for Today's Users (#IAC19)
danielanewman
229
22k
Stop Working from a Prison Cell
hatefulcrawdad
271
21k
A designer walks into a library…
pauljervisheath
207
24k
Transcript
Learning Functional Programming with JS @AnjanaVakil
The Recurse Center https://www.recurse.com/
What is functional programming?
What is functional programming? a programming paradigm
What is functional programming? a coding style
What is functional programming? a mindset
What is functional programming? a sexy, buzz-wordy trend
Why functional JavaScript?
Why functional JavaScript? object-oriented JS gets tricky (prototypes? this?!?)
Why functional JavaScript? safer, easier to debug/maintain
Why functional JavaScript? established community
OK, let’s do it!
OK, let’s do it! ...how?
Do everything with functions input -> output
Not functional: var name = “Anjana”; var greeting = “Hi,
I’m ”; console.log(greeting + name); => “Hi, I’m Anjana”
Functional: function greet(name) { return “Hi, I’m ” + name;
} greet(“Anjana”); => “Hi, I’m Anjana”
Avoid side effects use “pure” functions
Not pure: var name = “Anjana”; function greet() { console.log(“Hi,
I’m ” + name); }
Pure: function greet(name) { return “Hi, I’m ” + name;
}
Use higher-order functions functions can be inputs/outputs
function makeAdjectifier(adjective) { return function (string) { return adjective +
“ ” + string; }; } var coolifier = makeAdjectifier(“cool”); coolifier(“conference”); => “cool conference”
Don’t iterate use map, reduce, filter
http://www.datasciencecentral.com/forum/topics/what-is-map-reduce
Avoid mutability use immutable data
Mutation (bad!): var rooms = [“H1”, “H2”, “H3”]; rooms[2] =
“H4”; rooms; => ["H1", "H2", "H4"]
No mutation (good!): var rooms = [“H1”, “H2”, “H3”]; Var
newRooms = rooms.map(function (rm) { if (rm == “H3”) { return “H4”; } else { return rm; } }); newRooms; => ["H1", "H2", "H4"] rooms; => ["H1", "H2", "H3"]
Persistent data structures for efficient immutability Mori, Immutable.js
Ready to try it out?
FP libraries for JS • Mori (http://swannodette.github.io/mori/) • Immutable.js (https://facebook.github.
io/immutable-js/) • Underscore (http://underscorejs.org/) • Lodash (https://lodash.com/) • Ramda (http://ramdajs.com/) • ...and more!
Want to learn more?
“An introduction to functional programming” by Mary Rose Cook https://codewords.recurse.com/issues/one/an-introduction-to-functional-programming
Thanks for listening! I’m @AnjanaVakil Huge thanks to: JSUnconf organizers
Diversity sponsors The Recurse Center & alums