tomstuart

>> IF = -> b { b }
=> #<Proc:0x007fb4e4049cc8 (lambda)>

>> LEFT = -> p { p[-> x { -> y { x } } ] }
=> #<Proc:0x007fb4e403d680 (lambda)>

>> RIGHT = -> p { p[-> x { -> y { y } } ] }
=> #<Proc:0x007fb4e4028ff0 (lambda)>

>> IS_EMPTY = LEFT

tpolecat

scala> case class Bad(a: Int) { override def equals(a:Any) = true }
scala> val f = (n:Int) => Bad(n)
scala> val g = (b:Bad) => b.a

...

scala> Set(1,2,3).map(f andThen g)
res2: scala.collection.immutable.Set[Int] = Set(1, 2, 3)

scala> Set(1,2,3).map(f).map(g)

danieldietrich

Monad Laws

Let

• A, B, C be types
• unit: A -> Monad<A> a constructor
• f: A -> Monad<B>, g: B -> Monad<C> functions
• a be an object of type A
• m be an object of type Monad<a>

subfuzion

Common Options

-#, --progress-bar Make curl display a simple progress bar instead of the more informational standard meter.

-b, --cookie <name=data> Supply cookie with request. If no =, then specifies the cookie file to use (see -c).

-c, --cookie-jar <file name> File to save response cookies to.

jeroenvdgulik

The list is now hosted on a repository so you can PR -> https://github.com/jeroenvdgulik/awesome-talks/blob/master/README.md

The list

• Alberto Brandolini - Chasing Elephants https://youtu.be/klsksbDJOhI
• Erik Meijer - One Hacker Way https://youtu.be/FvMuPtuvP5w
• Erik Meijer - Category Theory, The essence of interface-based design https://youtu.be/JMP6gI5mLHc
• Gary Bernhardt - Wat https://www.destroyallsoftware.com/talks/wat
• Konstantin Kudryashov - Min-maxing Software Costs https://youtu.be/uQUxJObxTUs
• Marco Pivetta - Extremely Defensive PHP https://youtu.be/8d2AtAGJPno

jdegoes

Applied Functional Programming with Scala - Notes

Copyright © 2016-2018 Fantasyland Institute of Learning. All rights reserved.

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

mathiasverraes

module MonoidalFizzBuzz where
  
import Data.Monoid
import Data.Maybe

-- based on @mittie https://twitter.com/mittie/status/798257339736453120
monoidalFizzbuzz = zipWith fromMaybe numbers strings
  where
    fizzes = cycle [Nothing, Nothing, Just "Fizz"]
    buzzes = cycle [Nothing, Nothing, Nothing, Nothing, Just "Buzz"]

BalmungSan

Polymorphism in Scala

This document aims to show and compare three alternatives for achieving polymorphism in Scala.

• Subtyping, common in object-oriented languages like Java.
• Duck typing, common in dynamically typed languages like Python.
• Typeclasses, common in functional languages like Haskell.

Additionally, when implementing the typeclass pattern in Scala,

Daenyth

Parallels between map and similar functions

map          :: F[A] => (A =>     B)   => F[B]
flatMap      :: F[A] => (A =>   F[B])  => F[B]
traverse     :: G[A] => (A =>   F[B])  => F[G[B]]
flatTraverse :: G[A] => (A => F[G[B]]) => F[G[B]]
traverse_    :: F[A] => (A =>   F[B])  => F[Unit]

pchiusano

-- X filter
--  -- maybe some tests with List.all and List.any
-- 
-- intersperse
-- X head
-- X isEmpty
-- X tail
-- X init
-- X last