Kevin Meredith kevinmeredith

Thread Pools

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

CPU-bound
Blocking IO
Non-blocking IO polling

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

After scouring the internet and piece-mealing together the correct way to do this, here is a step-by-step, all-in-one-place guide to making logback STFU when running your unit tests.

Here's how to do it

Save the following as logback-test.xml under src/test/resources:

<configuration>
  <appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
    <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
      <pattern>%msg%n</pattern>

Advanced Functional Programming with Scala - Notes

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

Ever had the need to create a branch in a repo on Github without wanting (or being able) to access a local repo?

With the aid of [the Github API][1] and [hurl.it][2] this is a piece of cake!

Just follow these steps:

Open [http://hurl.it/][2]
Find the revision you want to branch from. Either on Github itself or by doing a GET request from Hurl: https://api.github.com/repos/<AUTHOR>/<REPO>/git/refs/heads
Copy the revision hash
Do a POST request from Hurl to https://api.github.com/repos///git/refs with the following as the POST body :

	import org.joda.time._
	import monix.execution._
	import monix.execution.Scheduler.Implicits.global
	import java.util.concurrent.TimeUnit
	import scala.util.control.NonFatal

	def scheduleOncePerDay(time: LocalTime, now: DateTime = DateTime.now())(cb: () => Unit)
	(implicit s: Scheduler): Cancelable = {

	val nextTick = {

	/*

	Overview
	--------

	To run a query using anorm you need to do three things:

	1. Connect to the database (with or without a transaction)
	2. Create an instance of `anorm.SqlQuery` using the `SQL` string interpolator
	3. Call one of the methods on `SqlQuery` to actually run the query

	// let's imagine you have an algebra that has a constructor like the following
	sealed trait Algebra[A]
	case class Ext[E, A](e: E, f: E => A) extends Algebra[A]

	/*
	* Not at all an uncommon pattern! Basically, this is going to show up any time you're
	* doing GADTs or GADT-like things, or any sort of type-aligned sequence (in any form).
	* The problem is that the pattern matcher affixes types in a linear fashion, and thus
	* will not unify the solution to E between the two parameters. For example:
	*/