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Type safety lobbyist

Lachezar Yankov lachezar

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Type safety lobbyist
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@lachezar
lachezar / Monads.scala
Last active February 12, 2024 15:36
Scala 3 Monad type class for Option and Either
trait Monad[M[_]] {
def pure[A](a: A): M[A]
def flatMap[A, B](m: M[A])(f: A => M[B]): M[B]
}
enum MyOption[+T]:
case None
case Some(value: T)
given Monad[MyOption] with
@lachezar
lachezar / IO.scala
Last active November 21, 2023 13:20
IO implementation exercise
case class IO[A](unsafeRun: () => A):
def map[B](f: A => B): IO[B] =
IO(() => f(unsafeRun()))
def flatMap[B](f: A => IO[B]): IO[B] =
IO(() => f(unsafeRun()).unsafeRun())
val io: IO[Int] = IO(() => {
println("Running side effect!!!")
@lachezar
lachezar / CheckedOptional.java
Created November 15, 2023 13:11
Java Optional that forces you to deal with the missing value on compile-time level instead of the runtime.
package org.example;
import java.util.Optional;
import java.util.Random;
import java.util.function.Supplier;
class NPEChecked extends Exception implements Supplier<NPEChecked> {
private static final NPEChecked instance = new NPEChecked();
@Override
@lachezar
lachezar / life.html
Created July 24, 2011 19:18
Game of Life (Javascript + HTML5's Canvas)
<!DOCTYPE html>
<html>
<head>
<title>Game of Life</title>
</head>
<body>
<canvas id="canvas" width="400" height="300">There should be a canvas somewhere here.... :-/</canvas>
<script type="text/javascript">
var canvas = document.getElementById('canvas');
var context = canvas.getContext('2d');
@lachezar
lachezar / currency_example.scala
Last active November 30, 2020 16:07
currency_example.scala
sealed trait Currency
case object Dollar extends Currency
case object Euro extends Currency
case class Money[T <: Currency](value: Int, currency: T) {
def +(that: Money[T]): Money[T] = {
Money[T](this.value + that.value, currency)
}
}
@lachezar
lachezar / currency_example.hs
Last active September 5, 2020 15:12
Currency in Haskell
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
module Main where
newtype USD = USD Int deriving (Show, Num)
newtype EUR = EUR Int deriving (Show, Num)
main :: IO ()
main = do
print $ (USD 12) + (USD 11)
@lachezar
lachezar / words.hs
Created October 5, 2019 19:21
Words in Haskell vs Typescript
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE QuasiQuotes #-}
module Lib
( run
) where
import Text.Regex.PCRE.Heavy
newtype Word' =
@lachezar
lachezar / config.exs
Created October 18, 2016 17:52
sample_config_kafka_ex
# This file is responsible for configuring your application
# and its dependencies with the aid of the Mix.Config module.
use Mix.Config
config :kafka_ex,
# a list of brokers to connect to in {"HOST", port} format
brokers: [
{"localhost", 9092}
],
# the default consumer group for worker processes, must be a binary (string)
@lachezar
lachezar / dict_to_object.py
Created January 19, 2014 14:03
Python dict to object
config_dict = {
'group1': {
'server1': {
'apps': ('nginx', 'mysql'),
'cpus': 4
},
'maintenance': True
},
'firewall_version': '1.2.3',
'python2.7': True
@lachezar
lachezar / _.sh
Last active December 17, 2015 06:58
Kick pylint on your python files and send notifications to osx notification center. It might be useful to get notified of nasty errors while you type your code...
kicker -e 'X="`pylint -r n **/*.py 2>/dev/null | tee /dev/tty | sed -n 2p`"; if [ -n "$X" ]; then curl -s -L -G --data-urlencode "message=$X" http://localhost:1337/fail; fi' **/*.py