# Scala

## Install

### Installers

These CLI utilities are used to fetch things we need.

- [SDKMan](https://sdkman.io/)
- [Coursier](https://get-coursier.io/)

### Java

We need a JDK, which SDKMAN is used for.

```bash
# List available JDKs
sdk ls java
```

Amazon seems to have a high-quality one.

- [Amazon Coretto](https://aws.amazon.com/corretto/)

Version 11 is the last LTS version.

```bash
sdk i java 11.0.10.9.1-amzn
```

### Build

#### sbt

- [sbt](https://www.scala-sbt.org/index.html)

```bash
sdk i sbt 1.5.0
```

#### Bloop

A system-wide build server that speeds compile times and can watch for changes and automatically recompile.

- [Bloop](https://scalacenter.github.io/bloop/)

```bash
cs install bloop --only-prebuilt=true
```

## New Project

Create a new Scala 3 project using the following template:

- [scala3.g8](https://github.com/scala/scala3.g8)

```bash
sbt new scala/scala3.g8
```

Change into your project directory and compile and run it using sbt.

```bash
sbt compile
sbt run
```

## SBT Plugins

The following plugins can be added to `project/plugins.sbt` to enhance the Scala coding experience.

### Code Formatting

- [Scalafmt](https://scalameta.org/scalafmt/)

```bash
cs install scalafmt
```

```scala
addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.4.0") // "2.4.0" is just sbt plugin version
```

Metals should automatically create a `.scalafmt.conf` file in the project root.  My settings:

```text
version = "2.7.4"
align.preset = more
maxColumn = 100
```

### better-monadic-for

| A Scala compiler plugin to give patterns and for-comprehensions the love they deserve.

- [better-monadic-for](https://github.com/oleg-py/better-monadic-for)

```scala
addCompilerPlugin("com.olegpy" %% "better-monadic-for" % "0.3.1")
```

## IDEs

#### VS Code

This extension will install everything it needs
- [Metals](https://scalameta.org/metals/)

## Watch, Compile, and Run

Use Bloop to watch for changes and automatically compile and run your program.  Your project should have a `.bloop` directory that contains a `<project>.json`, `<project>-test.json`, and a `<project>` subdirectory.  (Metals in VS Code will create this automatically.)  If it doesn't exist, you'll need to use `bloop project` to create one.

In one terminal session from within your project's root directory (the one that contains `.bloop`), run:

```bash
bloop compile -w <project>
```

From another terminal (same directory), run:

```bash
bloop run -w <project>
```

## Project Scaffolds

- [Scala 3 Giter8 Template](https://github.com/witt3rd/zio-dotty-quickstart.g8)
- [Scala 3 ZIO Starter](https://github.com/witt3rd/zio-starter)

## Language

- [Scala 3 Highlights (Dean Wampler)](https://deanwampler.github.io/scala3-highlights.html)
- [Rock the JVM](https://rockthejvm.com/)
- [Paolo Giarrusso—The DOT Calculus: An Introduction for Scala Programmers](https://www.youtube.com/watch?v=OVu7XzHY5U0)

## Ecosystem

### ZIO

- [ZIO](https://github.com/zio/zio)
  - [A Tour of ZIO](https://youtu.be/TWdC7DhvD8M)
    - [Scala 3 version](https://github.com/witt3rd/zio-tour) 
  - [Getting started with ZIO](https://youtu.be/6A1SA5Be9qw)
  - [Functional Programming 101 with Scala and ZIO - Functional World #3](https://youtu.be/gZMwjYTkK9k)
- [Prelude](https://github.com/zio/zio-prelude)
  - [SF Scala: Reimagining Functional Type Classes](https://youtu.be/OwmHgL9F_9Q)
- [CLI](https://github.com/zio/zio-cli)
- [Query](https://github.com/zio/zio-query)
- [Schema](https://github.com/zio/zio-schema)

### Misc

- [Scale By The Bay 2020: Juan Pablo Romero, A tour of String diagrams and Monoidal categories](https://youtu.be/CSFEzAgNJFM)