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@ant-arctica
ant-arctica / LinearLogic.hs
Last active July 3, 2023 13:22
Implementing linear logic (double negation, ...) in linear haskell using linear-base
{-# LANGUAGE BlockArguments #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE LinearTypes #-}
{-# LANGUAGE OverloadedRecordDot #-}
{-# LANGUAGE NoImplicitPrelude #-}
-- Quick demonstration that linear-base is enough to implement linear logic
import Data.Array.Destination
import Data.Array.Polarized.Pull
@mstewartgallus
mstewartgallus / onekappa.hs
Last active March 29, 2021 08:41
One object kappa/zeta calculus, kind of like reflexive objects but also weird
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE QuantifiedConstraints #-}
import Prelude hiding (id, (.))
import Control.Category
import Control.Monad.State hiding (lift)
class Category k => Terminal k where
term :: k a ()
{-# LANGUAGE AllowAmbiguousTypes #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeApplications #-}
module NamedTypeclass where
import Prelude hiding (Monoid, mempty, (<>))
@tomlokhorst
tomlokhorst / Optional+Unwrap.swift
Last active December 26, 2017 19:50
Unwrap multiple optionals in Swift 1.0
func unwrap<T1, T2>(optional1: T1?, optional2: T2?) -> (T1, T2)? {
switch (optional1, optional2) {
case let (.Some(value1), .Some(value2)):
return (value1, value2)
default:
return nil
}
}
func unwrap<T1, T2, T3>(optional1: T1?, optional2: T2?, optional3: T3?) -> (T1, T2, T3)? {
func main () {
let typedHeterogeneousList = true =+= "Hello" =+= 1 =+= HNil()
let first: Bool = typedHeterogeneousList.head()
let second: String = typedHeterogeneousList.tail().head()
let third: Int = typedHeterogeneousList.tail().tail().head()
}
protocol HList {
typealias Head
@sebastiaanvisser
sebastiaanvisser / g1.hs
Created May 29, 2013 08:36
Composing algebras using Arrow and Applicative.
{-# LANGUAGE GADTs, TypeOperators, TupleSections #-}
module Generics.Algebra where
import Control.Category
import Control.Arrow
import Control.Applicative
import Prelude hiding ((.), id)
import Generics.Combinator
@jonsterling
jonsterling / Coinduction.hs
Created October 13, 2012 22:46
Idea for codata syntax in Haskell
-- Inspired by http://www2.tcs.ifi.lmu.de/~abel/popl13.pdf
[codata|
codata Stream a where
head :: Stream a -> a
tail :: Stream a -> Stream a
|]
fib :: Stream Nat
[copattern|
@nfrisby
nfrisby / InductiveConstraints.hs
Created October 11, 2012 22:09
simple demo of "proving" in Haskell via singleton types
{-# LANGUAGE RankNTypes, TypeFamilies, DataKinds, TypeOperators,
ScopedTypeVariables, PolyKinds, ConstraintKinds, GADTs,
MultiParamTypeClasses, FlexibleInstances, UndecidableInstances,
FlexibleContexts #-}
module InductiveConstraints where
import GHC.Prim (Constraint)
@sebastiaanvisser
sebastiaanvisser / g0.hs
Created September 10, 2012 08:07
Composing algebras.
{-# LANGUAGE
GADTs
, KindSignatures
, RankNTypes
, TupleSections
, TypeOperators
#-}
module Generics.Morphism where
import Control.Arrow
@piscisaureus
piscisaureus / pr.md
Created August 13, 2012 16:12
Checkout github pull requests locally

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = git@github.com:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this: