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Central Virginia Scala Scholars

Agenda

1. Introductions
   • Name, company, kind of development, etc.
2. Discussion

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//  Comparison of using `null` vs `None` to represetn NAs

val csvtext = "1,4,5,6,,9,12"
val tokens = csvtext.split(",").toList
// Null NA Approach

val nullNAs = tokens.map(t => if(t.isEmpty) null else t)
val numFromNulled = for {
    t <- nullNAs
    num = if(t == null) null else t.toInt

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// NB: Requires SBT >= 0.13.5
package pomhelpers

import sbt._
import Keys._
import sbt.complete.Parser
import sbt.complete.DefaultParsers._

object ExtractMvnDependencies extends AutoPlugin {
    override def trigger = allRequirements

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import akka.actor._
import akka.stream.actor.ActorPublisher
import akka.stream.scaladsl._
import akka.stream.{ FlowMaterializer, MaterializerSettings }
import akka.testkit._
import org.scalatest.FunSpecLike

import scala.concurrent.Future
import scala.concurrent.duration._
class FutureMergeTest extends TestKit(ActorSystem()) with FunSpecLike with ImplicitSender {

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Here's one way of brute-force converting a bunch of Java code to Scala without too much concern for correctness.

Hard stuff is done by scalagen.

If the project is Maven-based with an existing pom.xml, all you need to do is run the scalagen Maven plugin:

mvn com.mysema.scalagen:scalagen-maven-plugin_2.10.1:0.3.2:main -DtargetFolder=target/scala

You have to have a pom.xml file for this to work. If your project is configured with sbt (or have no project!), use the sbt makePom task to create one:

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import sbt._
import sbt.Keys.commands
object OpenFolderHere extends AutoPlugin {
    override def trigger = allRequirements
    override lazy val projectSettings = Seq(
        commands += Command.command("openHere") { (state: State) =>
            "open .".!
            state
        }
    )

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addCommandAlias("package", "collectPackages")

addCommandAlias("stage", "universal:stage")

enablePlugins(GitBranchPrompt)

enablePlugins(JavaAppPackaging)

// TODO: Need to figure out how to look this up from the outer project
version in ThisBuild := "0.2.1-SNAPSHOT"

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"More computing sins are committed in the name of efficiency (without necessarily achieving it) than for any other single reason-including blind stupidity."
--W. A. Wulf

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#!/bin/bash
# Poor man's resource compiler
# Converts given file into compilable byte stream via
# C code header and implementation files.
# Based on original by http://www.linuxjournal.com/users/mitch-frazier
#

if [[ $# -ne 1 ]]; then
    echo "Usage: $0 FILENAME"
    exit 1

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<!-- Fragment from an Ant build.xml file for creating a disk image with bells and whistles. -->

        <property name="dmgname" value="${build.dir}/install-${name}.dmg" />
        <property name="tmpdmg" value="/tmp/${app.name}-installer-tmp.dmg" />
        <property name="volname" value="${app.name}-${VERSION}-Install" />

        <delete file="${tmpdmg}" quiet="yes" failonerror="false" />

        <!-- Create the temporary image -->
        <echo>Making initial image...</echo>