PureScript - Programming language

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PureScript is an open source programming language created in 2013 by Phil Freeman.

#76on PLDB

11Years Old

5kRepos

Download source code:

git clone https://github.com/purescript/purescript

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A strongly-typed language that compiles to JavaScript

Tags: programming language
PureScript is developed on GitHub and has 7,813 stars
There are at least 5,443 PureScript repos on GitHub
PureScript compiles to JavaScript
PureScript is written in PureScript, Haskell, JavaScript, Markdown, JSON, Bourne shell, YAML, CSS, Less, Yacc, Make, Dhall, XML
The Google BigQuery Public Dataset GitHub snapshot shows 382 users using PureScript in 826 repos on GitHub
There are 4 Project Euler users using PureScript
PureScript LSP implementation
GitHub supports syntax highlighting for PureScript
There is 1 Jupyter Kernel for PureScript
There is a central package repository for PureScript
4 PLDB concepts link to PureScript: mal, nulan, PureScript, Reason

Example from the web:

import Prelude
import Effect.Console (log)

greet :: String -> String
greet name = "Hello, " <> name <> "!"

main = log (greet "World")

Example from hello-world:

module Main where

import Debug.Trace

main = trace "Hello World"

Example from Linguist:

module Control.Arrow where

import Data.Tuple

class Arrow a where
  arr :: forall b c. (b -> c) -> a b c
  first :: forall b c d. a b c -> a (Tuple b d) (Tuple c d)

instance arrowFunction :: Arrow (->) where
  arr f = f
  first f (Tuple b d) = Tuple (f b) d

second :: forall a b c d. (Category a, Arrow a) => a b c -> a (Tuple d b) (Tuple d c)
second f = arr swap >>> first f >>> arr swap

swap :: forall a b. Tuple a b -> Tuple b a
swap (Tuple x y) = Tuple y x

infixr 3 ***
infixr 3 &&&

(***) :: forall a b b' c c'. (Category a, Arrow a) => a b c -> a b' c' -> a (Tuple b b') (Tuple c c')
(***) f g = first f >>> second g

(&&&) :: forall a b b' c c'. (Category a, Arrow a) => a b c -> a b c' -> a b (Tuple c c')
(&&&) f g = arr (\b -> Tuple b b) >>> (f *** g)

class ArrowZero a where
  zeroArrow :: forall b c. a b c

infixr 5 <+>

class ArrowPlus a where
  (<+>) :: forall b c. a b c -> a b c -> a b c

Language features

Feature	Supported	Example	Token
Strings	✓	"Hello world"	"
MultiLine Comments	✓	{- A comment -}	{- -}
Line Comments	✓	-- A comment	--
Semantic Indentation	✓	-- https://github.com/purescript/documentation/blob/master/language/Syntax.md -- Syntax is whitespace sensitive. The general rule of thumb is that declarations which span multiple lines should be indented past the column on which they were first defined on their subsequent lines. foo = bar + baz
Doc comments	✓	-- https://github.com/purescript/documentation/blob/master/language/Syntax.md -- \| `bool` performs case analysis for the `Boolean` data type, like an `if` statement. bool :: forall a. Boolean -> a -> a -> a bool true x _ = x bool false _ x = x
Comments	✓

HackerNews discussions of PureScript

title	date	score	comments
Show HN: PureScript - a functional language which compiles to Javascript	10/31/2013	2	0