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tkersey / Co.swift
Created Oct 15, 2019 — forked from bkase/Co.swift
Co.swift seems to work. Read NaturalSubclass.swift for what doesn't work, Natural.swift for what seems to work, and Co_old.swift for where it breaks down
View Co.swift
import Bow
// This version of Co seems to work even thoug it's a bit gross to deal with Any
// Think of this as an example of how to deal with rank2 type polymorphism -- you only
// deal with Any in the constructor, even `runCo` has a generic interface.
// newtype Co w a = Co (forall r. w (a -> r) -> r)
public final class ForCo {}
public final class CoPartial<W: Comonad>: Kind<ForCo, W> {}
public typealias CoOf<W: Comonad, A> = Kind<CoPartial<W>, A>
tkersey / FunDay.hs
Created Sep 30, 2019 — forked from gelisam/FunDay.hs
a concrete use for FunDay, the right-adjoint of Day
View FunDay.hs
-- A concrete use case for the type which is to '(->)' as 'Day' is to '(,)'.
-- I call it "FunDay", but I don't know what its proper name is. I've been
-- trying to find a use for 'FunDay', and I think I've found a pretty neat one.
{-# LANGUAGE FlexibleContexts, FlexibleInstances, PolyKinds, RankNTypes, TypeSynonymInstances #-}
module Main where
import Test.DocTest
import Control.Monad.Except
import Control.Monad.Reader
tkersey / UIView+Tooltips.h
Created Sep 13, 2019 — forked from steventroughtonsmith/UIView+Tooltips.h
WIP tooltips for Mac Catalyst
View UIView+Tooltips.h
// UIView+Tooltips.h
// Crossword
// Created by Steven Troughton-Smith on 13/09/2019.
// Copyright © 2019 Steven Troughton-Smith. All rights reserved.
#import <UIKit/UIKit.h>
tkersey / kan.lean
Created Sep 8, 2019 — forked from skaslev/kan.lean
Kan extensions
View kan.lean
def ran (g h : TypeType) (α : Type) := Π β, (α → g β) → h β
def lan (g h : TypeType) (α : Type) := Σ β, (g β → α) × h β
def mapr {g h} {α β} (s : α → β) (x : ran g h α) : ran g h β :=
λ b t, x b (t ∘ s)
def mapl {g h} {α β} (s : α → β) (x : lan g h α) : lan g h β :=
⟨x.1, ⟨s ∘ x.2.1, x.2.2⟩⟩
attribute [reducible] id
tkersey / equipment.hs
Created Sep 7, 2019 — forked from sjoerdvisscher/equipment.hs
Proarrow equipment in Hask
View equipment.hs
{-# LANGUAGE RankNTypes, TypeOperators, GADTs, ScopedTypeVariables, KindSignatures, DataKinds, FlexibleInstances, FlexibleContexts #-}
module Equipment where
import Data.Profunctor
import qualified Data.Profunctor.Composition as P
import Data.Singletons.Prelude.List
-- +--f--+
-- | v |
-- p--@--q
tkersey / Bindings.swift
Created Jun 8, 2019 — forked from AliSoftware/Bindings.swift
Re-implementation of @binding and @State (from SwiftUI) myself to better understand it
View Bindings.swift
// This is a re-implementation of the @Binding and @State property wrappers from SwiftUI
// The only purpose of this code is to implement those wrappers myself just to understand how they work internally and why they are needed
// Re-implementing them myself has helped me understand the whole thing better
//: # A Binding is just something that encapsulates getter+setter to a property
struct XBinding<Value> {
var value: Value {
get { return getValue() }
View TimeFormat.swift
public enum TimeFormat: String {
case twentyFourHour = "HH:mm"
case twelveHour = "h:mm a"
public init(_ locale: Locale = Locale.current) {
let is24Hour = DateFormatter
.dateFormat(fromTemplate: "j", options: 0, locale: locale)
.map { $0.contains("a") } ?? false
self = is24Hour ? .twentyFourHour : .twelveHour
View seemingly-impossible-swift-programs.swift
# Seemingly Impossible Swift Programs
# 1.) Completely possible programs
[1, 2, 3]
.allSatisfy { $0 >= 2 }
[1, 2, 3]
tkersey / ScrollDirection.swift
Created Dec 4, 2018
Use within scrollViewDidScroll
View ScrollDirection.swift
import UIKit
enum ScrollDirection: Int {
case up = -1
case none = 0
case down = 1
// MARK: - Determine
extension ScrollDirection {
tkersey /
Created Nov 14, 2018 — forked from mattmcneeney/
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