HelloWorld

This is a React Native application developed in Reason.

Installation

To get started, add the following scripts to your package.json:

"scripts": {
  "start": "node node_modules/react-native/local-cli/cli.js start",
  "build": "bsb -make-world -clean-world",
  "watch": "bsb -make-world -clean-world -w"
}

Next, run watch and start scripts from the command line so that both processes are running at the same time. This can be done with yarn (e.g. yarn watch) or npm (e.g. npm run watch).

The first script compiles you Reason code in a watch mode, meaning that every change is instantly recompiled.

Second one is a React Native packager that serves the compiled Reason code to the React Native client.

Hiding .bs.js files

Bucklescript compiles your Reason files to Javascript in source, meaning that App.re will result in App.bs.js file generated next to it.

These are build files and are by default ignored from the git repository.

If you are using VSCode, you can add the following to your workspace settings to hide them automatically:

{
  "files.exclude": {
    "**/*.bs.js": true
  }
}

Breakdown of existing files

The react-native init command generates a lot of boilerplate with files that might be not needed for your particular use case. Below is a breakdown of all top-level files to help you decide:

• .babelrc - required, for transpiling Javascript files to supported by the mobile engine Javascript version
• .buckconfig - optional, configuration files for Buck. Can be safely removed in most cases unless you are planning on using it
• .flowconfig - optional, used to configure Flow, which is a type checker for Javascript. Can be removed as we are writing our code in Reason now
• .watchmanconfig - optional, configuration for Watchman, which is a Facebook tool for listening to file system changes. This file is not needed, unless you plan on extending its configuration right now
• app.json - optional, usually generated when you eject from an Expo or create-react-native-app project. Can be removed without any issues

For more detailed instructions, please check the docs