Documentation map

Follow this development path to create a project and produce a datapack. The sidebar groups pages by development task and language feature.

Complete a project

1. Create a project: choose an ordinary project or a Java MNI project.
2. Develop in IDEA: edit, organize saved code, synchronize dependencies, and run tasks.
3. Configure the project: select the Minecraft version, directories, and compiler options.
4. Manage dependencies: add libraries and use lock files.
5. Build and inspect IR: find the datapack and trace compilation.

Find a language feature

Task	Guide
Declare variables, constants, and type aliases	Variables and types
Convert numbers and understand as and assignment	Conversions and type views
Define functions, default arguments, and extension syntax	Functions, Defaults and extensions
Use callbacks, implicit it, and trailing lambdas	Lambdas and function types
Transform, select, and accumulate values	Collection callbacks
Use read-only lists, NBT arrays, and integer ranges	Containers and ranges
Read and write game scores and NBT	ScoreRef and NBTRef
Select entities, change identity and position, and access passengers	Entities and contexts
Distinguish absent data from zero and read command results	Reading results
Define structured data and constructors	Data templates
Control property access	Properties and operators
Name a fixed set of choices	Enumerations
Share singleton state and type-related behavior	Singletons and companion objects
Use inheritance, abstract methods, and multiple parents	Inheritance
Write functions for several types	Generic functions and type parameters
Select object field types	Generic data templates
Supply fixed numeric configuration	Compilation parameters and known values
Specify generic parameter direction	in and out
Generate code for multiple Minecraft versions	Version conditions

Learn MNI

Start with a complete project. Read these pages in order:

1. Java MNI introduction: create a project and bind a Java method to an MCFPP function.
2. Parameters and results: receive ordinary and compilation parameters, then return MCFPP values.
3. Generate commands: produce operations that execute in the game.
4. Gradle and Java tests: configure dependencies and tests.

For libraries that combine expressions, loops, or user callbacks, continue with MNI macro introduction. It starts with call preparation, then covers parameters, callbacks, Minecraft operations, and template processors.

Read the API reference for annotation fields and entry signatures. Read Troubleshooting for tool configuration and synchronization problems.