rjchatfield’s gists

rjchatfield / plusMinus.swift

Created August 22, 2015 12:26

Adding generic ± operator in Swift

	typealias PlusMinusable = protocol<IntegerArithmeticType, ForwardIndexType>

	infix operator ± {}

	struct PlusMinus<T: PlusMinusable> {
	let value: T
	let variance: T
	var range: Range<T> {
	let lower = value - variance
	let upper = value + variance

rjchatfield / unwrapping.swift

Created July 28, 2015 14:00

Many ways to unwrap a cat

	let unwrapMe: [[Int]] = []

	// IF LET
	func unwrapWithIfLet (arrArr: [[Int]]) -> Int? {
	if let x = arrArr.first?.first {
	return x + 1
	}
	return nil
	}

rjchatfield / functors.js

Created February 1, 2015 13:52

Maybe, Either & Try Functors in ES6

	//--
	//-- FUNCTORS in ES6
	//--


	//-- BOILER PLATE

	let fmap = (f) => (functor) => functor.map(f);
	let c2 = (f2, f1) => (x) => f2(f1(x));
	let c3 = (f3, f2, f1) => (x) => f3(f2(f1(x)));

rjchatfield / highOrderFunc.js

Created January 24, 2015 09:16

Clean error handling network calls using high order functions in ES6

	/*
	==============================================================
	Clean error handling network calls using high order functions.

	ES6 version of:
	http://blog.carbonfive.com/2015/01/05/tidying-up-a-
	javascript-application-with-higher-order-functions/
	==============================================================
	*/

rjchatfield / transducers.swift

Last active January 13, 2019 13:41

Transducers & Reducers in Swift 2

	//-- This is an introduction to Transducers in Swift, inspired by
	// Talk: https://www.youtube.com/watch?v=estNbh2TF3E
	// Code: https://github.com/mbrandonw/learn-transducers-playground
	// Updated with Swift 2

	/**
	* Define a few test methods
	*/
	/// REDUCER
	func append <A> (xs: [A], x: A) -> [A] { return xs + [x] }

rjchatfield / transducers.js

Last active August 1, 2019 10:47

Transducers & Reducers in JavaScript

	//-- This is an introduction to Transducers in Javascript, inspired by
	// Talk: https://www.youtube.com/watch?v=estNbh2TF3E
	// Code: https://github.com/mbrandonw/learn-transducers-playground

	//-- Let's start by defining some reusable functions

	// Mappers // A => B
	square = (n) => n * n
	incr = (n) => n + 1
	// Filterers // A => Bool

rjchatfield / do_if_else_repeat_while_for.swift

Last active November 7, 2015 06:53

Do, If/ElseIf/If, While, Repeat/While, For in Swift (only using switch cases and recursion)

	typealias VoidFuncType = () -> Void
	typealias BoolFuncType = () -> Bool

	/**
	IF/ELSE STATEMENT
	*/
	typealias ElseIfType = (Bool, VoidFuncType) -> IfElse
	typealias ElseType = (VoidFuncType) -> Void

	struct IfElse {

rjchatfield / waterfall.coffee

Created December 8, 2014 22:05

Functional Waterfall Method

	# functional waterfall method
	waterfall = (scope) -> deploy(test(develop(design(analyse(scope)))))
	# or
	waterfall = (scope) -> compose(deploy, test, develop, design, analyse)(scope)
	# or
	waterfall = (scope) -> scope.analyse().design().develop().test().deploy()

rjchatfield / change_problem.coffee

Created December 6, 2014 09:18

FP solve the Change Problem

	#
	# FP solve the Change Problem
	# eg. myChange = calcChange(cost, myPayment)
	#

	# Used in fold() to build change object
	# Should be nested in calcChange, but is lifted for cleanliness
	coinAccStructure = (acc, coin) ->
	change = acc["payment"]
	acc[coin] = change % coin

rjchatfield / funfuns.coffee

Last active August 29, 2015 14:09

Functional Functions - "Quick look at common higher-order functions found in functional programs." https://bitbucket.org/rjchatfield/functional-functions

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