noughtmare’s gists

noughtmare / StrictUntil.hs

Created November 8, 2023 23:07

Why no strict until'?

noughtmare / FastEffects.hs

Last active November 8, 2023 22:42

The fastest effect system approaches translate operations into a fast concrete monad like IO or State.

	{-# LANGUAGE UnboxedTuples #-}

	import Control.Monad
	import Test.Tasty.Bench
	import Data.IORef

	{-# NOINLINE countdownIO #-}
	countdownIO :: IO Integer -> (Integer -> IO ()) -> IO Integer
	countdownIO get put = go where
	go = do

noughtmare / CFG.hs

Created August 14, 2023 21:01

Exteremely naive CFG parser

	import Data.List qualified as List
	import Test.Tasty.Bench.Fit (fit, mkFitConfig)

	data CFG = CFG String [(String, [Symbol])]

	data Symbol = T Char \| NT String

	splits :: String -> [(String, String)]
	splits [] = [([], [])]
	splits (x : xs) = ([], x : xs) : map (\(y, z) -> (x : y, z)) (splits xs)

noughtmare / log

Created May 29, 2023 12:50

	these 30 derivations will be built:
	/nix/store/8bp2iihry7scnlnsw240v71ydh70agg7-bash-5.1-p16.drv
	/nix/store/fdsax0a1p3wqnnwb4gsxzr1y55yhgc77-binutils-2.39.drv
	/nix/store/sr0jdc6c0cj5chrgzbvvsci9w64scns0-libxcrypt-4.4.30.drv
	/nix/store/4jjh8kxnbk60x84nz6wzfsnyp2fgdp64-perl-5.36.0.drv
	/nix/store/s8srp5k52fbgn168b8nlmdrndsyc76v6-perl5.36.0-gettext-1.07.drv
	/nix/store/v8f4lwzmcgiwk0680aa2z1cd8c7zmhrl-help2man-1.49.2.drv
	/nix/store/z0har4q95p7pagbd3755qi5ans8zihn0-libtool-2.4.7.drv
	/nix/store/76n41vykcagiza65nv8kcy4xvr9yzif1-hook.drv
	/nix/store/ipfm2lrrbdj9w6vl2j4w0qj9p9jp73zm-acl-2.3.1.drv

noughtmare / LeftRecursiveRecognizers.hs

Last active May 24, 2023 15:00

Parser combinator-style recognizers which allow for left-recursion.

	{-# LANGUAGE PatternSynonyms #-}

	import Control.Monad.State
	import Data.Foldable (traverse_)

	type Id = String
	newtype Parser = Parser { alts :: [P] }
	data P = T Char Parser \| NT Id Parser Parser \| Success

	success :: Parser

noughtmare / FinalFreeEffects.hs

Created April 28, 2023 12:28

Alternative record-based/final implementation of effects using a free monad

	{-# LANGUAGE QuantifiedConstraints #-}
	{-# OPTIONS_GHC -Wall #-}

	import Control.Arrow ((>>>))
	import Control.Monad

	data Free f a = Pure a \| Free (f (Free f a))

	deriving instance Functor f => Functor (Free f)
	instance Functor f => Applicative (Free f) where

noughtmare / TypeLevelScopeSafety.hs

Created April 23, 2023 10:27

Scope safe lambda calculus using type level programming in Haskell

	{-# LANGUAGE DataKinds #-}
	{-# LANGUAGE TypeFamilies #-}
	{-# LANGUAGE UndecidableInstances #-}
	{-# LANGUAGE OverloadedLabels #-}

	import GHC.TypeLits
	import Data.Kind
	import GHC.OverloadedLabels
	import Data.Function ((&))

noughtmare / ReifiedEmbeddedAbstractSyntax.hs

Last active April 11, 2023 15:09

Convenient embedded abstract syntax for Haskell.

	{-# LANGUAGE TypeFamilies #-}
	{-# LANGUAGE BlockArguments #-}
	{-# LANGUAGE QuantifiedConstraints #-}
	{-# OPTIONS_GHC -Wall #-}

	import Data.Reify ( reifyGraph, MuRef(..), Graph(..))
	import Data.Function (fix)
	import Data.IntMap.Strict qualified as Map
	import Data.Foldable ( Foldable(toList) )
	import Data.Bifunctor ( Bifunctor(second) )

noughtmare / GLL.hs

Last active May 16, 2023 06:43

Moved to: https://github.com/noughtmare/gigaparsec

	{-# LANGUAGE OverloadedStrings #-}
	{-# LANGUAGE ScopedTypeVariables #-}
	{-# LANGUAGE GADTs #-}
	{-# LANGUAGE StandaloneDeriving #-}
	{-# LANGUAGE DeriveFunctor #-}
	{-# LANGUAGE TypeFamilies #-}
	{-# LANGUAGE InstanceSigs #-}
	{-# LANGUAGE RankNTypes #-}
	{-# LANGUAGE UndecidableInstances #-}
	{-# LANGUAGE DerivingVia #-}

noughtmare / ApplicativeObservableSharing.hs

Last active April 6, 2023 12:27

A prototype of parser combinators which support left recursion.

	{-# LANGUAGE ExplicitNamespaces #-}
	{-# LANGUAGE GADTs #-}
	import Control.Applicative
	import Data.Type.Equality ( type (:~:)(..) )
	import Unsafe.Coerce ( unsafeEqualityProof, UnsafeEquality(UnsafeRefl) )
	import Control.Monad

	newtype Name a = Name ID

	type ID = Int

Jaro noughtmare