mushtaq

// comparing to kotlin version: https://proandroiddev.com/extension-classes-f9dcf5878b71

sealed trait Feature
object SomeFeature extends Feature

trait AppFeatures {
  def isEnabled(feature: Feature): Boolean
}

extension (appFeatures: AppFeatures) 

mushtaq

/**
 * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
 */
package akka.contrib.mailbox

import scala.concurrent.duration._
import java.util.concurrent.atomic.AtomicInteger
import java.util.concurrent.atomic.AtomicLong
import com.typesafe.config.Config
import akka.actor.{ ActorContext, ActorRef, ActorSystem, ExtendedActorSystem }

mushtaq

package flowcontrol

import scala.concurrent.duration._

import akka.actor.typed.ActorRef
import akka.actor.typed.ActorSystem
import akka.actor.typed.Behavior
import akka.actor.typed.scaladsl.Behaviors

/**

mushtaq

import math._
val (h, w) = (Page.canvas.height, Page.canvas.width)
var x = 0.0
// $FiddleStart
val graphs = Seq[(String, Double => Double)](
  ("red", sin),
  ("green", x => 2 - abs(x % 8 - 4)),
  ("blue", x => 3 * pow(sin(x / 12), 2) * sin(x))
)
// $FiddleEnd

mushtaq

Principled Meta Programming for Scala

This note outlines a principled way to meta-programming in Scala. It tries to combine the best ideas from LMS and Scala macros in a minimalistic design.

• LMS: Types matter. Inputs, outputs and transformations should all be statically typed.

• Macros: Quotations are ultimately more easy to deal with than implicit-based type-lifting

• LMS: Some of the most interesting and powerful applications of meta-programming

mushtaq

import java.util.concurrent._
import akka.dispatch.{Dispatcher, ExecutorServiceDelegate}
import config.Config
import helpers.ScalaLogger

class ExecutionContextMonitor()(implicit metricsService: MetricsClient, config: Config) {
  private val log = ScalaLogger.get(this.getClass)

  private val scheduler = Executors.newSingleThreadScheduledExecutor()

mushtaq

import akka.http.scaladsl.model.HttpHeader
import akka.http.scaladsl.model.HttpMethods._
import akka.http.scaladsl.model.HttpResponse
import akka.http.scaladsl.model.headers.`Access-Control-Allow-Credentials`
import akka.http.scaladsl.model.headers.`Access-Control-Allow-Methods`
import akka.http.scaladsl.model.headers.`Access-Control-Allow-Origin`
import akka.http.scaladsl.model.headers.Origin
import akka.http.scaladsl.server.Directive0
import akka.http.scaladsl.server.Directives._
import akka.http.scaladsl.server.MethodRejection

mushtaq

// [info] Running p.Run
// List(Fish(Bob, Esq.,12), Kitty(Thor, Esq.,java.awt.Color[r=255,g=200,b=0]))

package misc

import java.awt.Color

trait Pet[A] {
  def name(a: A): String
  def renamed(a: A, newName: String): A

mushtaq

/** This is in reference to @tploecat's blog http://tpolecat.github.io/2015/04/29/f-bounds.html
 *  where he compares F-bounded polymorphism and type classes for implementing "MyType".
 * 
 *  Curiously, the in my mind obvious solution is missing: Use abstract types.
 * 
 *  A lot of this material, including an argument against F-bounded for the use-case
 *  is discussed in:
 * 
 *  Kim B. Bruce, Martin Odersky, Philip Wadler:

mushtaq

/*
This example uses Scala.  Please see the MLlib documentation for a Java example.

Try running this code in the Spark shell.  It may produce different topics each time (since LDA includes some randomization), but it should give topics similar to those listed above.

This example is paired with a blog post on LDA in Spark: http://databricks.com/blog
Spark: http://spark.apache.org/
*/