After listening to the latest Magic Read-along episode "You should watch this" (which you should go listen to now) I got
caught up thinking about Brian's idea of an Endomorphism version of Kleisli composition for use with Redux,
it's actually a very similar model to what I'm using in my event
framework for event listeners so I figured I'd try to formalize the pattern and recognize
some of the concepts involved. IIRC Brian
described the idea of a Redux-reducer, which is usually of type s -> Action -> s, it takes a state and an action and returns
a new state. He then re-arranged
the arguments to Action -> s -> s. He then recognized this as Action -> Endo s (an Endo-morphism is just any function
from one type to itself: a -> a).
He would take his list of reducers and partially apply them with the Action, yielding a list of type Endo s where s
Brandon Kase bkase
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| // | |
| // Operators.swift | |
| // FastParsing | |
| // | |
| // Created by Chris Eidhof on 26/12/2016. | |
| // Copyright © 2016 objc.io. All rights reserved. | |
| // | |
| // TODO: give appropriate credit. Many parts were stolen from SwiftParsec. |
jdegoes
/ Applied-FP-with-Scala.md
Last active
May 9, 2024 08:27
Copyright © 2016-2018 Fantasyland Institute of Learning. All rights reserved.
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