djspiewak

type ∀[F[_]] = scalaz.Forall[F]

/**
 * An unpublished arbitrary type.  May be viewed as a formulation of
 * (∃ α . α).  Thus, we encode a rank-1 universal by means of a rank-2
 * existential.  This encoding is more convenient for our purposes.
 */
sealed trait τ

object τ {

olafurpg

import sbt._, Keys._
import scala.xml.{Node => XmlNode, NodeSeq => XmlNodeSeq, _}
import scala.xml.transform.{RewriteRule, RuleTransformer}
import sbt.plugins.JvmPlugin

object PPrintPlugin extends AutoPlugin {
  override def requires = JvmPlugin
  override def trigger: PluginTrigger = AllRequirements
  override def projectSettings: Seq[Def.Setting[_]] = List(
    libraryDependencies ++= {

d1egoaz

If you want to learn Scala, I’d suggest:

• Install IntelliJ + Scala Plugin
• Don’t do the Coursera courses yet.
• Don’t do the “red book” Functional Programming in Scala yet.
• Do: http://underscore.io/books/
  • Essential Scala
  • Essential Play
  • Essential Slick
• Do Scala for the Impatient: https://www.amazon.com/Scala-Impatient-Cay-S-Horstmann/dp/0321774094
• The Neophyte’s Guide to Scala http://danielwestheide.com/scala/neophytes.html

mandubian

// Build Scala source code
val tree = q"""
object Test {  
  val a = 2 + 5
  def f(b: String) = { b + a.toString }
}
"""
val src = List(TreeNode(tree))

// Build Scala target code

lihaoyi

import play.api.libs.json.Json

object Main{
  def main(args: Array[String]): Unit = {
    println(
      Json.prettyPrint(
        Json.toJson(Seq("Hello", "World", "Cow"))
      )
    )
  }

tallclair

apiVersion: extensions/v1beta1
kind: PodSecurityPolicy
metadata:
  name: restricted
  annotations:
    seccomp.security.alpha.kubernetes.io/allowedProfileNames: 'docker/default'
    apparmor.security.beta.kubernetes.io/allowedProfileNames: 'runtime/default'
    seccomp.security.alpha.kubernetes.io/defaultProfileName:  'docker/default'
    apparmor.security.beta.kubernetes.io/defaultProfileName:  'runtime/default'
spec:

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

non

introduction

ScalaCheck 1.14.0 was just released with support for deterministic testing using seeds. Some folks have asked for examples, so I wanted to produce a Gist to help people use this feature.

simple example

These examples will assume the following imports:

karanlyons

private rule Macho
{
    meta:
        description = "private rule to match Mach-O binaries (copied from Apple's XProtect)"
    condition:
        uint32(0) == 0xfeedface or uint32(0) == 0xcefaedfe or uint32(0) == 0xfeedfacf or uint32(0) == 0xcffaedfe or uint32(0) == 0xcafebabe or uint32(0) == 0xbebafeca
}

rule ZoomDaemon
{