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
Let's talk about PureScript
Search
Kārlis Lauva
August 17, 2016
Programming
0
70
Let's talk about PureScript
Presentation at Frontend Meetup Riga, August 2016.
Kārlis Lauva
August 17, 2016
Tweet
Share
More Decks by Kārlis Lauva
See All by Kārlis Lauva
Going Full Monty with full.monty
karlis
1
90
The Transatlantic Struggle
karlis
0
61
Two Scoops of Scala
karlis
0
99
Valsts pārvaldes atvērto datu semantiskās integrācijas procesi
karlis
1
140
Tornado in 1 Hour (or Less)
karlis
4
180
Other Decks in Programming
See All in Programming
AI時代におけるSRE、 あるいはエンジニアの生存戦略
pyama86
6
1.2k
デザインパターンで理解するLLMエージェントの作り方 / How to develop an LLM agent using agentic design patterns
rkaga
3
320
Jakarta EE meets AI
ivargrimstad
0
660
エンジニアとして関わる要件と仕様(公開用)
murabayashi
0
310
Figma Dev Modeで変わる!Flutterの開発体験
watanave
0
150
watsonx.ai Dojo #4 生成AIを使ったアプリ開発、応用編
oniak3ibm
PRO
1
180
Compose 1.7のTextFieldはPOBox Plusで日本語変換できない
tomoya0x00
0
200
OnlineTestConf: Test Automation Friend or Foe
maaretp
0
120
React への依存を最小にするフロントエンド設計
takonda
12
3.2k
CSC509 Lecture 12
javiergs
PRO
0
160
CSC509 Lecture 09
javiergs
PRO
0
140
Better Code Design in PHP
afilina
PRO
0
130
Featured
See All Featured
It's Worth the Effort
3n
183
27k
Product Roadmaps are Hard
iamctodd
PRO
49
11k
Making Projects Easy
brettharned
115
5.9k
RailsConf & Balkan Ruby 2019: The Past, Present, and Future of Rails at GitHub
eileencodes
131
33k
Save Time (by Creating Custom Rails Generators)
garrettdimon
PRO
27
840
Speed Design
sergeychernyshev
25
620
Bootstrapping a Software Product
garrettdimon
PRO
305
110k
Rails Girls Zürich Keynote
gr2m
94
13k
ReactJS: Keep Simple. Everything can be a component!
pedronauck
665
120k
The Straight Up "How To Draw Better" Workshop
denniskardys
232
140k
Keith and Marios Guide to Fast Websites
keithpitt
409
22k
I Don’t Have Time: Getting Over the Fear to Launch Your Podcast
jcasabona
28
2k
Transcript
an exciting trip through history prelude
1936 Lambda Calculus is born
1990 A bunch of smart people start working Haskell
1995 Brendan Eich is hired by NetScape to write Scheme
for the browser
Spoiler alert: He doesn't write a Scheme for NetScape
2016
You shouldn't be sad.
Maybe those functional dudes got something right.
let's talk about purescript Kārlis Lauva @skazhy frontend rīga meetup,
2016
Hello. I write Clojure and dabble with other things This
is not a monad tutorial This is, like, my opinion
So, Haskell for the browser, eh
module Main where import Prelude import Control.Monad.Eff import Control.Monad.Eff.Console sup
:: String -> String sup g = "sup, " ++ g main :: forall e. Eff (console :: CONSOLE | e) Unit main = do log $ sup "world"
None
(function(exports) { "use strict"; var Prelude = PS["Prelude"]; var Control_Monad_Eff
= PS["Control.Monad.Eff"]; var Control_Monad_Eff_Console = PS["Control.Monad.Eff.Console"]; var sup = function (g) { return "sup, " + g; }; var main = Control_Monad_Eff_Console.log(sup("world")); exports["main"] = main; exports["sup"] = sup;; })(PS["Main"] = PS["Main"] || {}); PS["Main"].main();
Y
turns out, functional programming languages are really useful for web
things
but javascript too can be purely functional
None
let's discuss the bad parts
[Object object]
an *actual* type system
purescript makes this example boring
like, really boring
sketchy branching
None
None
pattern matching
data Behavior = KillHumans | BeNiceToHumans type Robot = {
naughty :: Boolean } interactWithHumans :: Robot -> Behavior interactWithHumans { naughty: true } = KillHumans interactWithHumans { naughty: false } = BeNiceToHumans
data Behavior = KillAllHumans | BeNiceToHumans | KillOnlyVapers type Robot
= { niceness :: Int } interactWithHumans :: Robot -> Behavior interactWithHumans { niceness: 0 } = KillAllHumans interactWithHumans { niceness: 1 } = KillOnlyVapers interactWithHumans _ = BeNiceToHumans
callback hell
monads
fetchRobots(function(response) { assembleFleet(function(robots) { if (robots) return robots; }, function(error
{ .. }); }, function(error) {... });
data RobotArmy = Army (List Robot) fetchRobots = do robotParts
<- get "/robotParts" robots <- assembleFleet robotParts return $ Army robots
None
does purescript survive in the real world?
yes.
None
ecosystem and tooling
psc short for "purescript compiler"
modules managed via bower
• build tool => pulp • hoogle for purescript =>
pursuit
purescript - javascript teamwork
back to killer robots
data Behavior = KillHumans | BeNiceToHumans instance showBehavior :: Show
Behavior where show KillHumans = "kill all humans11" show BeNiceToHumans = "humans, you are pretty tite" type Robot = { naughty :: Boolean } interactWithHumans :: Robot -> Behavior interactWithHumans { naughty: true } = KillHumans interactWithHumans { naughty: false } = BeNiceToHumans safeInteract :: Boolean -> String safeInteract x = show $ interactWithHumans { crazyMurderer : x }
PS.Main.safeInteract(isCrazyMurderingRobot)();
but will purescript react?
yes.
ok, so what have we learned
so should we all switch to purescript today?
not _all_ of us
most of the internet runs on vanilla javascript just fine
(for years)
None
None
go check it out hack cool things
• purescript.org • karlis.me
thanks