tomekw

# app/channels/hello_channel.rb
class HelloChannel < ActionCable::Channel::Base
  def say_hello(data)
    times_to_say_hello = data.fetch("times_to_say_hello")
    hello = "Hello, #{current_profile.name}!"

    times_to_say_hello.times do
      ActionCable.server.broadcast(current_profile.id, hello)
    end
  end

tomekw

// file: src/main/kotlin/com/_98elements/Calculator.kt

package com._98elements

object Calculator {
    fun add(a: Int, b: Int) = a + b

    fun divide(a: Int, b: Int) = a / b
}

tomekw

$ ./gradlew test

> Task :test FAILED

com._98elements.CalculatorSpec > adds 2 to 2 FAILED
    org.opentest4j.AssertionFailedError at CalculatorSpec.kt:11

3 tests completed, 1 failed

FAILURE: Build failed with an exception.

tomekw

$ ./gradlew test

BUILD SUCCESSFUL in 2s
3 actionable tasks: 2 executed, 1 up-to-date

tomekw

// build.gradle

buildscript {
    // use specific Kotlin version
    ext.kotlin_version = '1.2.61'
}

plugins {
    // install Kotlin JVM gradle plugin
    id 'org.jetbrains.kotlin.jvm' version '1.2.61'

tomekw

// settings.gradle

rootProject.name = 'calculator'

tomekw

// file: src/test/kotlin/com/_98elements/CalculatorSpec.kt

package com._98elements

import org.junit.jupiter.api.Assertions.assertEquals
import org.junit.jupiter.api.assertThrows
import org.spekframework.spek2.Spek
import org.spekframework.spek2.style.specification.describe

object CalculatorSpec: Spek({

tomekw

Keybase proof

I hereby claim:

• I am tomekw on github.
• I am tomekw (https://keybase.io/tomekw) on keybase.
• I have a public key whose fingerprint is E3DF 760E C16C 936E B949 11C2 081B 19A1 2D4C 4A8E

To claim this, I am signing this object:

tomekw

> require "digest/bubblebabble"
=> true
> Digest::SHA256.bubblebabble("_tomekw")
=> "xihag-nivyk-lucah-zekek-segyg-dimib-zeken-mepov-cilet-cegah-coteg-vipit-mybyg-cehor-kerec-gylyf-vaxux"

tomekw

• statically-typed
• strongly-typed
• only one way to do one thing
• no "syntax shortcuts" (cryptic operators, etc.)
• immutability (value "classes", collections)
• pattern matching
• higher-order functions
• readable syntax (lisp-case a.k.a. kebab-case indentifiers, do...end, def, etc.)
• no need for an IDE
• native binaries (optionally statically-linked)