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

coreyhaines

module Flow exposing (Flow(..), map, withDefault, mapDefault, view, update)

import Html


type Flow state
    = NotRunning
    | Running state

i-am-tom

-- ## An Elm-entary visualisation
-- by _Tom Harding_

module Main exposing (..)

-- This project uses a few dependencies. To anyone who's written any
-- amount of Elm before, the only stranger is `AnimationFrame`, from
-- the `elm-lang/animation-frame` package. This lets us subscribe to
-- the browser's RAF API. Everything else should be fairly obvious:
-- `Html` / `Svg` for our view, `Http` / `Json.Decode` for the AJAX

coreyhaines

module Editable exposing (..)


type Editable ofType
    = NotEditing { value : ofType }
    | Editing { originalValue : ofType, buffer : ofType }


value : Editable ofType -> ofType
value editable =

rofrol

Elm best practices

Style guide

• http://package.elm-lang.org/help/design-guidelines
• http://elm-lang.org/docs/style-guide
• https://github.com/NoRedInk/elm-style-guide
• https://gist.github.com/laszlopandy/c3bf56b6f87f71303c9f
• https://github.com/ohanhi/elm-style-guide

swlaschin

Functional Track talks from NDC London 2017

Also, here is the list of all videos from NDC London 2017:

• YouTube
• Vimeo

Wednesday 2017-01-18

mrange

Railway Oriented Programming and F# Result

Full source: https://gist.github.com/mrange/aa9e0898492b6d384dd839bc4a2f96a1

Option<_> is great for ROP (Railway Oriented Programming) but we get no info on what went wrong (the failure value is None which carries no info).

With the introduction F# 4.1 we got Result<_, _> a "smarter" Option<_> as it allows us to pass a failure value.

However, when one inspects the signature of Result.bind one sees a potential issue for ROP:

danidiaz

from ubuntu:latest

run apt-get update && \
    apt-get install -y emacs agda-mode agda-stdlib && \
    apt-get install -y coq coqide && \
    apt-get install -y openssh-server && \
    apt-get install -y iproute2 wget curl && \
    apt-get install -y bzip2 tmux git vim libgmp-dev python3 gcc libtinfo-dev zlib1g-dev xz-utils make && \
    git config --global core.editor vim && \
    git config --global alias.co checkout && \