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Alexey Kuleshevich lehins

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lehins / MutInt.hs
Created April 6, 2023 22:46 — forked from TerrorJack/MutInt.hs
{-# LANGUAGE GHCForeignImportPrim #-}
{-# LANGUAGE MagicHash #-}
{-# LANGUAGE UnboxedTuples #-}
{-# LANGUAGE UnliftedFFITypes #-}
module MutInt
( MutInt,
newMutInt,
getMutInt,
putMutInt,
@lehins
lehins / hip.hs
Created December 8, 2016 00:58
Image processing sample in Haskell using HIP
-- install Haskell Image Processing library using `$ cabal install hip`
import qualified Graphics.Image as I
import Graphics.Image.Processing (rotate180)
import qualified Graphics.Image.Interface as IM
import qualified Graphics.Image.Interface.Repa as R
import Graphics.Image.ColorSpace
import Graphics.Image.Types
@lehins
lehins / get-stack.sh
Created November 17, 2020 14:20
Custom version of https://get.haskellstack.org/
#!/bin/sh -e
#
# Stack installation script.
#
# This script is meant for quick & easy install via:
# 'curl -sSL https://get.haskellstack.org/ | sh'
# or:
# 'wget -qO- https://get.haskellstack.org/ | sh'
#
# By default, this installs 'stack' to '/usr/local/bin'.
@lehins
lehins / git-modtime.hs
Last active March 19, 2020 00:21
Restore file and directory modification time to the commit time
{-# LANGUAGE CPP #-}
#if __GLASGOW_HASKELL__ < 802
main :: IO ()
main = do
let (ghcMaj, ghcMin) = divMod (__GLASGOW_HASKELL__ :: Int) 100
ghcVer = show ghcMaj ++ "." ++ show ghcMin
putStrLn $ "GHC version: " ++ ghcVer ++ " is not supported by git-modtime script."
#else
import Data.Time.Format (parseTimeM, iso8601DateFormat, defaultTimeLocale)
import System.Directory (setModificationTime)
@lehins
lehins / safe-decimal.hs
Created February 10, 2020 13:25
Example usage of safe-decimal package
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE NumericUnderscores #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
module Lib where
import Control.Monad.State.Strict
import Control.Exception
@lehins
lehins / TypeLevelMoney.hs
Created January 16, 2020 01:26
Currency and money at type level
{-# LANGUAGE AllowAmbiguousTypes #-}
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE GADTs #-}
{-# LANGUAGE KindSignatures #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeApplications #-}
@lehins
lehins / fail-vs-case.hs
Created July 17, 2019 17:52
name <- atomically $ do
readTVar (currentUpdate ctxt) >>= \case
name:names <- readTVar (queuedUpdates ctxt)
writeTVar (queuedUpdates ctxt) names
return name
name <- atomically $ do
readTVar (currentUpdate ctxt) >>= \case
Just _ -> retry
Nothing -> readTVar (queuedUpdates ctxt) >>= \case
@lehins
lehins / safe-decimal.md
Last active January 24, 2019 22:02
Performance of safe-decimal backed by Int64 and Word64

Addition

Name 1 10 100 1000 10000 100000 1000000
Int 6.712 ns 11.81 ns 0.066 μs 0.606 μs 11.19 μs 0.112 ms 1.118 ms
Double 13.95 ns 29.11 ns 0.247 μs 2.272 μs 22.35 μs 0.224 ms 2.233 ms
Integer 46.33 ns 251.5 ns 1.296 μs 12.71 μs 126.4 μs 1.309 ms 19.36 ms
@lehins
lehins / cache-s3-ec2.tf
Last active January 8, 2019 00:10
Setting up EC2 instance and S3 bucket for cache-s3
terraform {
backend "s3" {
encrypt = "true"
bucket = "my-remote-tfstate-bucket"
key = "my-remote-tfstate/ec2/terraform.tfstate"
region = "us-east-1"
}
}
@lehins
lehins / stack-build-loop.hs
Created November 24, 2018 09:00
An infinite loop that runs `stack build` periodically killing it and restarting it again until either finished or build error occurs.
#!/usr/bin/env stack
{- stack
--resolver lts-12.2 script
--package filepath
--package rio
--package bytestring
--package time
--package random
--package process
--package unix