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Remove sbt section from getting started (scala#3086)
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* Remove sbt section from getting started

* add link to sbt and maven tutorials, reintroduce IDE sections
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@bishabosha @sila-strike
bishabosha authored and sila-strike committed Oct 27, 2024
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127 changes: 50 additions & 77 deletions _overviews/getting-started/install-scala.md
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Expand Up @@ -164,7 +164,7 @@ string to standard output.
To run the program, execute `scala run hello.scala` command from a terminal, within the `<project-dir>` directory. The file will be compiled and executed, with console output
similar to following:
```
$ scala run hello.scala
$ scala run hello.scala
Compiling project (Scala {{site.scala-3-version}}, JVM (20))
Compiled project (Scala {{site.scala-3-version}}, JVM (20))
Hello, World!
Expand All @@ -187,7 +187,7 @@ the content of the `name` argument.

To pass the arguments when executing the program, put them after `--`:
```
$ scala run hello.scala -- Gabriel
$ scala run hello.scala -- Gabriel
Compiling project (Scala {{site.scala-3-version}}, JVM (20))
Compiled project (Scala {{site.scala-3-version}}, JVM (20))
Hello, Gabriel!
Expand Down Expand Up @@ -216,7 +216,7 @@ sequence of paths.

Execute the program. The dependency will be automatically downloaded. The execution should result in a similar output:
```
$ scala run counter.scala
$ scala run counter.scala
Compiling project (Scala {{site.scala-3-version}}, JVM (20))
Compiled project (Scala {{site.scala-3-version}}, JVM (20))
4
Expand Down Expand Up @@ -246,127 +246,100 @@ You can execute code interactively using the REPL provided by the `scala` comman
$ scala
Welcome to Scala {{site.scala-3-version}} (20-ea, Java OpenJDK 64-Bit Server VM).
Type in expressions for evaluation. Or try :help.
scala>
scala>
```

Write a line of code to be executed and press enter.
```
scala> println("Hello, World!")
Hello, World!
scala>
scala>
```

The result will be printed immediately after executing the line. You can declare values:
```
scala> val i = 1
val i: Int = 1
scala>
scala>
```

A new value of type `Int` has been created. If you provide an expression that can be evaluated, its result will be stored in an automatically created value.
```
scala> i + 3
val res0: Int = 4
scala>
scala>
```
You can exit the REPL with `:exit`.

### Next steps

Now that you have tasted a little bit of Scala, you can either explore the language itself, or learn how to set up a project using the
sbt and an IDE using the tutorials below. If you want to familiarize yourself with the language more, consider checking out:

* [The Scala Book](/scala3/book/introduction.html) (see the Scala 2 version [here](/overviews/scala-book/introduction.html)), which provides a set of short lessons introducing Scala’s main features.
* [The Tour of Scala](/tour/tour-of-scala.html) for bite-sized introductions to Scala's features.
* [Learning Resources](/learn.html), which includes online interactive tutorials and courses.
* [Our list of some popular Scala books](/books.html).

## Create a "Hello World" project with sbt

Once you have installed sbt, you are ready to create a Scala project, which
is explained in the following sections.
## Using an IDE

To create a project, you can either use the command line or an IDE.
If you are familiar with the command line, we recommend that approach.
> You can read a short summary of Scala IDEs on [a dedicated page](/getting-started/scala-ides.html).
### Using the command line

sbt is a build tool for Scala. sbt compiles, runs,
and tests your Scala code. (It can also publish libraries and do many other tasks.)
Let's use an IDE to open the code we wrote above. The most popular ones are [IntelliJ](https://www.jetbrains.com/idea/) and
[VSCode](https://scalameta.org/metals/docs/editors/vscode).
They both offer rich IDE features, but you can still use [many other editors](https://scalameta.org/metals/docs/editors/overview.html).

To create a new Scala project with sbt:
### Prepare the project

1. `cd` to an empty folder.
1. Run the command `sbt new scala/scala3.g8` to create a Scala 3 project, or `sbt new scala/hello-world.g8` to create a Scala 2 project.
This pulls a project template from GitHub.
It will also create a `target` folder, which you can ignore.
1. When prompted, name the application `hello-world`. This will
create a project called "hello-world".
1. Let's take a look at what just got generated:
First, remove all the using directives, and put them in a single file `project.scala` in the `<project-dir>` directory.
This makes it easier to import as a project in an IDE:

```scala
//> using scala {{site.scala-3-version}}
//> using toolkit 0.5.0
```
- hello-world
- project (sbt uses this for its own files)
- build.properties
- build.sbt (sbt's build definition file)
- src
- main
- scala (all of your Scala code goes here)
- Main.scala (Entry point of program) <-- this is all we need for now
```

More documentation about sbt can be found in the [Scala Book](/scala3/book/tools-sbt.html) (see [here](/overviews/scala-book/scala-build-tool-sbt.html) for the Scala 2 version)
and in the official sbt [documentation](https://www.scala-sbt.org/1.x/docs/index.html)

### With an IDE

You can read a short summary of Scala IDEs on [a dedicated page](/getting-started/scala-ides.html)

## Open hello-world project

Let's use an IDE to open the project. The most popular ones are [IntelliJ](https://www.jetbrains.com/idea/) and
[VSCode](https://scalameta.org/metals/docs/editors/vscode).
They both offer rich IDE features, but you can still use [many other editors](https://scalameta.org/metals/docs/editors/overview.html).
> Optionally, you can re-initialise the necessary IDE files from within the `<project-dir>` directory with the command `scala setup-ide .`, but these files will already exist if you have previously run the project with the Scala CLI `run` command.
### Using IntelliJ

1. Download and install [IntelliJ Community Edition](https://www.jetbrains.com/help/idea/installation-guide.html)
1. Install the Scala plugin by following [the instructions on how to install IntelliJ plugins](https://www.jetbrains.com/help/idea/discover-intellij-idea-for-scala.html)
1. Open the `build.sbt` file then choose *Open as a project*
1. Open the `<project-dir>` directory, which should be imported automatically as a BSP project.

### Using VSCode with metals
### Using VSCode with Metals

1. Download [VSCode](https://code.visualstudio.com/Download)
1. Install the Metals extension from [the Marketplace](https://marketplace.visualstudio.com/items?itemName=scalameta.metals)
1. Next, open the directory containing a `build.sbt` file (this should be the directory `hello-world` if you followed the previous instructions). When prompted to do so, select *Import build*.
1. Next, open the `<project-dir>` directory in VSCode. Metals should activate and begin importing the project automatically.

### Play with the source code

View these two files in your IDE:
View these three files in your IDE:

- _project.scala_
- _hello.scala_
- _counter.scala_

You should notice the benefits of an IDE, such as syntax highlighting, and smart code interactions.
For example you can place the cursor over any part of the code, such as `os.pwd` in _counter.scala_ and documentation for the method will appear.

When you run your project in the next step, the configuration in _project.scala_ will be used to run the code in the other source files.

- _build.sbt_
- _src/main/scala/Main.scala_
### Run the code

When you run your project in the next step, the configuration in _build.sbt_ will be used to run the code in _src/main/scala/Main.scala_.
If you’re comfortable using your IDE, you can run the code in _counter.scala_ from your IDE.
Attached to the `countFiles` method should be a prompt button. Click it to run the method. This should run without issue.
The `hello` method in _hello.scala_ needs arguments however, so will require extra configuration via the IDE to provide the argument.

## Run Hello World
Otherwise, you can run either application from the IDE's built-in terminal as described in above sections.

If you’re comfortable using your IDE, you can run the code in _Main.scala_ from your IDE.
## Next steps

Otherwise, you can run the application from a terminal with these steps:
Now that you have tasted a little bit of Scala, you can further explore the language itself, consider checking out:

1. `cd` into `hello-world`.
1. Run `sbt`. This opens up the sbt console.
1. Type `~run`. The `~` is optional and causes sbt to re-run on every file save,
allowing for a fast edit/run/debug cycle. sbt will also generate a `target` directory
which you can ignore.
* [The Scala Book](/scala3/book/introduction.html) (see the Scala 2 version [here](/overviews/scala-book/introduction.html)), which provides a set of short lessons introducing Scala’s main features.
* [The Tour of Scala](/tour/tour-of-scala.html) for bite-sized introductions to Scala's features.
* [Learning Resources](/learn.html), which includes online interactive tutorials and courses.
* [Our list of some popular Scala books](/books.html).

When you’re finished experimenting with this project, press `[Enter]` to interrupt the `run` command.
Then type `exit` or press `[Ctrl+D]` to exit sbt and return to your command line prompt.
There are also other tutorials for other build-tools you can use with Scala:
* [Getting Started with Scala and sbt](/getting-started/sbt-track/getting-started-with-scala-and-sbt-on-the-command-line.html)
* [Using Scala and Maven](/tutorials/scala-with-maven.html)

## Getting Help
There are a multitude of mailing lists and real-time chat rooms in case you want to quickly connect with other Scala users. Check out our [community](https://scala-lang.org/community/) page for a list of these resources, and for where to reach out for help.

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