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Vlad Patryshev vpatryshev

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vmarquez / TxMapTest.scala
Last active Nov 28, 2021
A mini STM if you will. I've made a'Transactional' map that mutates in a referentially transparent way.
View TxMapTest.scala
import java.util.concurrent.atomic.AtomicReference
import java.util.concurrent.CountDownLatch
import scala.concurrent.Future
import scala.concurrent.ExecutionContext
object TxMapTest {
* Example Usage
* We want to show two threads working with the same data source having both of their effects succeed
alvinj /
Last active Jun 22, 2021
A shell script to create an SBT project directory structure
# Name: sbtmkdirs
# Version: 1.5
# Purpose: Create an SBT project directory structure with a few simple options.
# Author: Alvin Alexander,
# License: Creative Commons Attribution-ShareAlike 2.5 Generic
jaytaylor / EnvHacker.scala
Created Aug 21, 2014
Setting environment variables in Scala JVM
View EnvHacker.scala
trait EnvHacker {
* Portable method for setting env vars on both *nix and Windows.
* @see
def setEnv(newEnv: Map[String, String]): Unit = {
try {
val processEnvironmentClass = Class.forName("java.lang.ProcessEnvironment")
val theEnvironmentField = processEnvironmentClass.getDeclaredField("theEnvironment")
kristopherjohnson /
Last active Aug 15, 2020
Translation of classic Lunar Lander game from FOCAL to Rust
//! Translation of
//! <>
//! by Jim Storer from FOCAL to Rust.
use std::error::Error;
use std::io;
use std::io::prelude::*;
use std::marker::{Send, Sync};
use std::process;
use std::str::FromStr;
tmyymmt / HexBytesUtil.scala
Created Sep 15, 2012
hex2bytes and bytes2hex fixed
View HexBytesUtil.scala
object HexBytesUtil {
def hex2bytes(hex: String): Array[Byte] = {
hex.replaceAll("[^0-9A-Fa-f]", "").sliding(2, 2), 16).toByte)
def bytes2hex(bytes: Array[Byte], sep: Option[String] = None): String = {
sep match {
case None =>"%02x".format(_)).mkString
case _ =>"%02x".format(_)).mkString(sep.get)
retronym / config.scala
Last active May 9, 2018
Styles of config propagation: Manual, Implicits, DynamicVariable, Reader
View config.scala
package scalaz.example
object Reader extends App {
* Manual propagation of the environment (in the example, `contextRoot`.)
object Config0 {
def fragment1(contextRoot: String) = <a href={contextRoot + "/foo"}>foo</a>
View LinVect.scala
object LinVect {
type K = Double
trait NAT[N] { val nat: Int }
def NAT[N: NAT]: NAT[N] = implicitly
def nat[N: NAT]: Int = NAT[N].nat
trait NAT_10
implicit object NAT_10 extends NAT[NAT_10]
zraffer / CAT.scala
Created Nov 6, 2016
sample of abuse of Java/Scala type system for simulate given formal system
View CAT.scala
package cat
object CAT {
// system traits
sealed trait Type[Self <: Type[Self]]
sealed trait Of[Self <: Of[Self, T], T <: Type[T]]
// types
case class Ob()
zraffer / package.scala
Last active Apr 26, 2017
a few operations with functors
View package.scala
package object types {
import scala.language.reflectiveCalls
import scala.language.higherKinds
// quantifiers aka (co)ends
type Forall[+F[_]] = { def apply[X]: F[X] }
type Exists[+F[_]] = F[_]
// basic categorical notions
zraffer / CCC.scala
Created Nov 4, 2016
Scala Types are objects of Cartesian Closed Category
View CCC.scala
// Scala Types are objects of Cartesian Closed Category
// (w/o equalities, probably not a category, sorry)
object CCC {
// category structure
def id[T0]: T0=>T0 = x0=>x0
def mul[T1, T2, T3](f23: T2=>T3, f12: T1=>T2): (T1=>T3) = x1 => f23(f12(x1))
// terminal object; adjunction;
type _1_ = Unit