Martynas Mickevičius 2m

Advent of Code 2019, in Unison

Spoilers for Advent of Code 2019 follow.

Day 1: The Tyranny of the Rocket Equation

Fuel required to launch a given module is based on its mass. Specifically, to find the fuel required for a module, take its mass, divide by three, round down, and subtract 2.

This describes a simple function. There seems to be an oversight in the problem statement that modules with very low mass have a negative fuel requirement. I'm going to assume that's not right, and that instead of integer subtraction, we want natural number subtraction (sometimes called "monus"). In Unison, we can use the Nat type instead of integers, so we don't have to consider negatives. The subtraction operation is called drop:

Summer of Usability

Dear Community

We from the Scala team at Lightbend have decided to take some time this summer to work on usability improvements that are always falling through the cracks while we're busy working on the hard features of the next Scala release. Here is a summary of our project proposals.

REPL usability improvements

@som-snytt already implemented the JLine 3 upgrade (scala/scala#8036) which gives multi-line history and editing. We are planning to add further improvements (many of them pioneered by Ammonite and/or the Dotty REPL) on top of this, for example syntax highlighting and import library dependencies.

Akka Streams Backpressure Gauge

Measures if there is backpressure on an Akka Stream at the given stage.

Motivation

When an Akka Stream doesn't perform as intended, it is difficult to tell where the bottleneck is, since all stages operate at the same rate (see e.g. here ).

So when things are not fast as expected, this pressure gauge can help you to narrow down on the slow stage. Imagine

	#!/bin/bash

	# Colors
	RED='\033[0;31m'
	GREEN='\033[0;32m'
	NO_COLOR='\033[0m'
	BLUE='\033[0;34m'
	YELLOW='\033[0;33m'
	NO_COLOR='\033[0m'

	//> using scala 3.3

	import scala.util.{Failure, NotGiven, Success, Try, boundary}
	import boundary.{Label, break}
	import scala.annotation.targetName

	/**
	* Proof of concept implementation of a syntax similar to Kotlin and
	* typescript. Within the context provided by [[getEither]], you can call
	* `?` on any optional/failable type (currently supports [[Option]],

	const MY_DOMAIN = "help.splitbee.io"
	const START_PAGE = "https://www.notion.so/splitbee/Help-Center-bbf26e2b70574901b9c98e5d11e449de"

	addEventListener('fetch', event => {
	event.respondWith(fetchAndApply(event.request))
	})

	const corsHeaders = {
	"Access-Control-Allow-Origin": "*",
	"Access-Control-Allow-Methods": "GET, HEAD, POST,PUT, OPTIONS",

	const MY_DOMAIN = "agodrich.com"
	const START_PAGE = "https://www.notion.so/gatsby-starter-notion-2c5e3d685aa341088d4cd8daca52fcc2"
	const DISQUS_SHORTNAME = "agodrich"

	addEventListener('fetch', event => {
	event.respondWith(fetchAndApply(event.request))
	})

	const corsHeaders = {
	"Access-Control-Allow-Origin": "*",

	/* library dependecies
	"org.xerial" % "sqlite-jdbc" % "3.23.1",
	"org.tpolecat" %% "doobie-core" % "0.5.3",
	"org.tpolecat" %% "doobie-hikari" % "0.5.3", // HikariCP transactor.
	"org.tpolecat" %% "doobie-specs2" % "0.5.3", // Specs2 support for typechecking statements.
	"org.tpolecat" %% "doobie-scalatest" % "0.5.3", // ScalaTest support for typechecking statements.
	*/
	object TryDoobie extends App {

	import doobie._

	/**
	* Copyright (C) 2018 Lightbend Inc. <http://www.lightbend.com>
	*/
	package akka.stream.stage

	import scala.collection.immutable
	import scala.concurrent.duration.FiniteDuration

	import akka.NotUsed
	import akka.annotation.InternalApi

	/* sbt -- Simple Build Tool
	* Copyright 2011 Mark Harrah, Eugene Yokota
	*/
	package sbt
	package myinspect

	import java.io.File

	import Def.{ScopedKey, compiled, flattenLocals}