justinwoo

Go to this link: https://purescript-resources.readthedocs.io/en/latest/0.11.7-to-0.12.0.html

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There are some changes you will need to make for most applications to be upgraded to PureScript 0.12. With some usage of editor commands, you should be able to convert any 20K LOC codebase in less than an hour.

Libraries

• Remove eff, install effect
• Remove dom and dom-*, use web-dom and such from purescript-web. Use type holes (?whatmethod) to discover new APIs

SystemFw

cats-effect

The cats-effect project defines a purely functional effect type (IO[A]), and associated typeclasses defining its behaviour. The ones we care about for this example are:

trait Sync[F[_]] extends MonadError[F, Throwable] {
   def delay[A](a: => A): F[A]
   ...
}

gvolpe

Shared State in pure Functional Programming

Newcomers to Functional Programming are often very confused about the proper way to share state without breaking purity and end up having a mix of pure and impure code that defeats the purpose of having pure FP code in the first place.

Reason why I decided to write up a beginner friendly guide :)

Use Case

We have a program that runs three computations at the same time and updates the internal state to keep track of the

Daenyth

package teikametrics

import cats.effect.implicits._
import cats.effect.{ContextShift, ExitCase, Sync, Timer}
import cats.syntax.all._

import scala.concurrent.ExecutionContext
import scala.concurrent.duration.FiniteDuration

object JavaFuture {

djspiewak

Collections Redesign Proposal

I'm going to start off by motivating what I'm doing here. And I want to be clear that I'm not "dissing" the existing collections implementation or anything as unproductively negative as that. It was a really good experiment, it was a huge step forward given what we knew back in 2.8, but now it's time to learn from that experiment and do better. This proposal uses what I believe are the lessons we can learn about what worked, what didn't work, and what is and isn't important about collections in Scala.

This is going to start out sounding really negative and pervasively dismissive, but bear with me! There's a point to all my ranting. I want to be really clear about my motivations for the proposal being the way that it is.

Problems

Generic Interfaces