Scalawags #29

thescalawags's podcast

Scalawags #29: Scala Days recap and news

YouTube link: https://www.youtube.com/watch?v=r-QSTPOKyDM

Your hosts: Josh Suereth, Dick Wall, Daniel Spiewak, Seth Tisue.

Yup, we're Heatherless again. We promise you Heather next episode.

Join us during (and between) episodes for web-based Scalawags chat on Gitter.

Intro #1 (0:00)

• our amateur beatboxing is not improving

Daniel's accident (0:15)

• Daniel's brain is all better now
• but hear him tell the story of the cat, the clothesline, and his emergency room visit

Josh in Tron space (3:35)

• demoing his terminal application that renders your webcam live in ASCII art, using Akka streams
  • https://github.com/jsuereth/streamerz
• what, no speech bubbles? alas, audio-on-the-JVM

Intro #2 (5:50)

• hi, we're the Scalawags
• Scala Days: all five of us were there together, and Lukas took a photo, but we didn't have time to do an episode
• nostalgia for the modem yodel

Scala Days keynotes (9:50)

• all the talk videos are at https://www.parleys.com/channel/scala-days-san-francisco-2015
• we liked the "go change the world" keynotes by Danese Cooper and Dianne Marsh
  • https://www.parleys.com/tutorial/keynote-tuesday-scala-days-2015-san-francisco
  • https://www.parleys.com/tutorial/technical-leadership-from-wherever-you
• Dick reveals which parts of his intro of Danese were actually outrageous lies
• bombshells in Martin's keynote? well, Hascalator. don't forget Hascalator.
  • https://www.parleys.com/tutorial/scala-where-came-from-where-its-going
• more details on TASTy (Martin's proposal for delivering Scala libraries not as JARs, but as Typed Abstract Syntax Trees). but don't hold your breath

Monad transformers (17:50)

• bit at the end of Martin's keynote about representing effects in the type system, because monad transformers make everyone's heads explode
• or do they? discuss.
• try to unify subtyping and parametric polymorphism and all hell breaks loose
• new Typesafe proposal to speed up the Scala compiler by replacing it with Mechanical Turk

Scala Days favorites (26:10)

• Daniel liked Andrew Phillips' Scala Puzzlers talk
  • https://www.parleys.com/tutorial/scala-puzzlers-matrix-anything-possible
  • Daniel got a lot of them wrong, and so did Adriaan and Miles
• Dick liked Julie Pitt's "If I Only Had a Brain... In Scala"
  • https://www.parleys.com/tutorial/only-had-brain-scala
• Dick has seen Brendan McAdams's "A Skeptic's Look at scalaz' "Gateway Drugs"" talk before and liked it
  • https://www.parleys.com/tutorial/a-skeptics-look-scalaz-gateway-drugs

What libraries should I use? (29:20)

• Functional Reactive Programming, what it is or isn't, and how Josh wrote an ASCII Pong game with it, but with only one paddle and no ball
• Josh's effort at a beginner talk, on Scala libraries newcomers should know about. sharing the ecosystem lore
• Daniel: there'll never be a complete reference; people should just ask on IRC or Gitter
• or it could be like apps: "Enjoying Scalaz? Give us a five-star review!"

Why didn't my talk get in? (42:00)

• beginner, intermediate, or advanced?
• Seth liked Joe Barnes' Type-level Programming in Scala 101" talk
  • https://www.parleys.com/tutorial/type-level-programming-scala-101
  • advanced topic, beginner-friendly presentation. so what is it, beginner or advanced?
• why didn't your talk get in?
  • there were a ton of submissions
  • everyone sent "reactive" proposals
  • everyone's proposals were "intermediate"
  • your abstract was way too long
  • your abstract was way too short
  • who are you? you had no bio
  • Josh thinks you're a jerk

More Scala Days favorites (57:25)

• Seth liked Chris Vogt's "Compossible: Extensible Records and Type-Indexed Maps"
  • https://www.parleys.com/tutorial/scala-records-extensible-records-type-indexed-maps
  • giving the type system a more flexible idea of what fields are present in data
• Seth liked Miles Sabin's talk on automatic derivation of typeclass instances
  • https://www.parleys.com/tutorial/swiss-army-knife-generic-programming-shapeless-typeclass-type-class-action
  • look ma, no macros! well, one shared behind-the-scenes macro, but the new stuff is all implicits built over it
• don't macro everything. what should you macro?
• TASTy: are macros expanded, in the trees?
• Daniel liked Vlad Ureche's miniboxing talk, "Project Valhalla: The Good, the Bad and the Ugly"
  • https://www.parleys.com/tutorial/project-valhalla-the-good-bad-ugly
  • that's "oo-ray-kay", more or less, but call him Vlad
  • Project Valhalla involves bringing something like specialization to the JVM so Java can use it. but Scala should use it too. we want to write abstract code and have it run fast even for primitive types.
• Scala Days had killer wi-fi

Conclusion/roundup (1:11:50)

• Scala Days Amsterdam coming up
• Escalate training coming up
  • http://escalatesoft.com
• S'mores and type lambdas!
• Tweet your Phil Bagwell Award nominations to @scaladays
  • no Typesafers, no EPFL-ers
• the SLIP (Scala Library Improvement Process) committee had their first monthly meeting
  • SLIP talk now on Gitter at https://gitter.im/scala/slip
• Josh selects self, highlights self
• sock puppet pantomime preview of episode #30

(photo by Lukas Rytz)