JRuby  
  Scala

Why Ruby?

Why Scala?

Learn more at scala-tour.com

What makes learning Scala easy?

What makes learning Scala hard?

Tooling

JRuby → Scala (Easier)

Scala → JRuby (Harder)

slides.map(_.learnings).sum

future { ruby.scala() }

– Le fin –

Find this project under github.com/RubyAndScala/jruby_meets_scala

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require("test.rb")

// Sending methods via .send or Dynamic trait
eval("[1,2,3]").send[Long](`length) must beEqualTo(3)
eval("[1,2,3]").length must beEqualTo(3)

// Ruby reflection in Scala
eval[RubyObj]("[]").isA_?(`Array) must beTrue
eval[RubyObj]("[]").respondTo_?(`length) must beTrue

// obj(something) is forwared to obj[something]
eval("['foo','bar','baz']")(0) must beEqualTo("foo")
eval("{ :foo => 1, :bar => 2, :baz => 3 }")(`foo) must beEqualTo(1)

// Cast to trait/interface via .as[TraitName]
trait Person {
  def firstname: String
  def firstname_=(f: String): Unit
}
val zaphod:Person = new RubyObject(`Person, "Zaphod").as[Person]
zaphod.firstname must beEqualTo("Zaphod")
zaphod.firstname = "The Zeeb"

In Scala, how do you…