gvolpe

ThisBuild / scalaVersion := "2.13.5"

lazy val root = (project in file("."))
  .settings(
    name := "minimal",
    libraryDependencies ++= Seq(
      compilerPlugin(
        "org.typelevel" %% "kind-projector" % "0.11.3"
          cross CrossVersion.full
      ),

fancellu

import scala.util.Random

// Simple example of an IO effect Monad, no Cats

object MyIO extends App{

  // IO encapsulates a side effecting operation

  final class IO[A](val run: () => A) {
    def map[B](f: A => B): IO[B] = IO(f(run()))

amrali

// Example program
#include <iostream>
#include <string>
#include <vector>
#include <type_traits>
 
//---------------------
// Maybe and MyVector, two totally unrelated classes whose only commanilty is that they are both type constructors of the same arity (e.g. 1) and order (e.g. 1).
//---------------------
template< typename T >

djspiewak

Quick Tips for Fast Code on the JVM

I was talking to a coworker recently about general techniques that almost always form the core of any effort to write very fast, down-to-the-metal hot path code on the JVM, and they pointed out that there really isn't a particularly good place to go for this information. It occurred to me that, really, I had more or less picked up all of it by word of mouth and experience, and there just aren't any good reference sources on the topic. So… here's my word of mouth.

This is by no means a comprehensive gist. It's also important to understand that the techniques that I outline in here are not 100% absolute either. Performance on the JVM is an incredibly complicated subject, and while there are rules that almost always hold true, the "almost" remains very salient. Also, for many or even most applications, there will be other techniques that I'm not mentioning which will have a greater impact. JMH, Java Flight Recorder, and a good profiler are your very best friend! Mea

djspiewak

Thread Pools

Thread pools on the JVM should usually be divided into the following three categories:

1. CPU-bound
2. Blocking IO
3. Non-blocking IO polling

Each of these categories has a different optimal configuration and usage pattern.

jonnyjava

The Pragmatic Programmer: From Journeyman to Master

Tips collected

1. Care About Your Craft

• Why spend your life developing software unless you care about doing it well?

2. Think! About Your Work

• Turn off the autopilot and take control. Constantly critique and appraise your work.

3. Provide Options, Don't Make Lame Excuses

• Instead of excuses, provide options. Don't say it can't be done; explain what can be done.

Avaq

const I  = x => x
const K  = x => y => x
const A  = f => x => f (x)
const T  = x => f => f (x)
const W  = f => x => f (x) (x)
const C  = f => y => x => f (x) (y)
const B  = f => g => x => f (g (x))
const S  = f => g => x => f (x) (g (x))
const S_ = f => g => x => f (g (x)) (x)
const S2 = f => g => h => x => f (g (x)) (h (x))

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

seratch

organization := "net.seratch"

name := "sandbox"

version := "0.1"

scalaVersion := "2.9.1"

libraryDependencies ++= Seq(
  "junit"          % "junit"     % "4.9"   withSources(),