Script REPL Addon (1.21, 1.20) – MCPE/Bedrock Mod

Script REPL Addon (read-eval-print loop) is a powerful debugging tool for Minecraft Scripting, enabling users to execute JavaScript code within Minecraft: Bedrock Edition. This versatile add-on is perfect for debugging, prototyping, and learning both JavaScript and Minecraft’s scripting API.

Features:

Currently, JavaScript is the only programming language that allows developers to use Script APIs from within their code.

This add-on allows developers to debug JavaScript code and report an error condition immediately in Minecraft in-game using this interpreter. This reduces the amount of script errors happen in your code development and time and allows developers to experiment with the new features available in Script API modules in Minecraft.

Learning Minecraft Script API

You are advised to learn JavaScript free from online courses available online before learning how to use Minecraft’s Scripting API. Check out the download page for more information.
There are a somewhat decent amount of resources available online related to script API:

• Sample GameTests from Microsoft – Sample GameTest behavior files for Minecraft Bedrock Edition. Minecraft supports GameTests – a combination of JavaScript + MCStructures – for validating facets of Minecraft behavior.
• Official Script API Documentation – Microsoft’s official documentation of high-level introduction of experimental Script API
• Script API Examples – JavaScript code snippets that use Script API modules only
• Jayly’s Script API Documentation – Jayly’s Script API documentation with guides and easy-to-use and easy-to-understand API references for programming beginners.

Here are some examples of executing JavaScript in-game:

Example #1:

Example #2:

To get started:

1. You can get the ‘JavaScript REPL [Use]’ item through chat command !javascript (available on all interpreter builds) or script event command /scriptevent interpreter:js (available on non-experimental interpreter builds)
2. Use the enchantment book with the name ‘JavaScript REPL [Use]’ to open the interpreter
3. Type your javascript code in the form. Multi-line supported.
4. Press “Submit” button to start executing your code

In case you want to disable your code, you have to run /reload command which requires operator permission to execute the command.

Script Block

Note: This feature is only available behind beta versions of the interpreter.

If you want to have multiple JavaScript codes stored in the world, a script block helps you store the JavaScript code similar to a command block. However, the code can only be executed by the player who interacted and press ‘Submit’ button in the form.

The code data will not be lost from the block moving with pistons unless the block is destroyed by an explosion or breaking blocks.

Modules Included:

The following Script API modules are compatible with this Addon:

Script REPL (Beta APIs):

• @minecraft/server
• @minecraft/server-ui
• @minecraft/server-gametest
• @minecraft/debug-utilities

Script REPL (Latest):

• @minecraft/server
• @minecraft/server-ui

Installation Note:

Make sure you turn on Experimental Gameplay.

Script REPL Addon Download Links

For Minecraft PE/Bedrock 1.21

mcaddon: Download from server 1 – Download from server 2

For Minecraft PE/Bedrock 1.20

mcaddon: Download from server 1 – Download from server 2