RedScript 3.0 Released

Published: March 2026

RedScript 3.0 is here — a major release with 7 new optimizer passes, language improvements, and complete stdlib documentation.

Highlights

🚀 Optimizer Pipeline

The compiler now includes 15 optimization passes:

New in 3.0	Description
Tail Call Optimization	Converts tail recursion to loops (avoids MC's ~512 depth limit)
Common Subexpression Elimination	Caches repeated expressions
Auto-Inline	Inlines functions ≤5 MIR instructions
Execute Chain Optimization	Merges execute if A run execute if B → execute if A if B
Strength Reduction	x * 2 → x + x
Scoreboard Read Batching	Deduplicates redundant reads
NBT Write Coalescing	Removes overwritten writes

Enable with -O2 for full optimization:

redscript build main.mcrs -O2

🆕 Language Features

Struct extends:

struct Enemy { hp: int }
struct Boss extends Enemy { name: string }
// Boss has both hp and name fields

Labeled break/continue:

'outer: for (let i = 0; i < 10; i = i + 1) {
    for (let j = 0; j < 10; j = j + 1) {
        if (found) break 'outer;
    }
}

New decorators:

Decorator	Description
@memoize	LRU-1 caching for int functions
@throttle(N)	Rate-limit to once per N ticks
@retry(N)	Auto-retry on failure
@test	Mark test functions

🛠️ CLI Improvements

Command	New in 3.0
redscript test	Run @test functions
redscript publish	Package as .zip datapack
redscript lint	5 static analysis rules
redscript.toml	Project config file

📚 Complete Documentation

All 50 stdlib modules now have full documentation with:

• /// doc comments for every function
• @param, @returns, @example annotations
• English and Chinese versions
• Auto-generated from source

New modules: queue, map, set_int, sets

🔧 LSP Enhancements

• Hover docs: Shows doc comments on hover
• Lint diagnostics: Real-time warnings in editor
• Source maps: Trace .mcfunction back to .mcrs

Upgrading

npm install -g redscript-mc@3.0.0

Breaking Changes

1. format_string type is now unified as string — remove any as string casts
2. arr.len() for literal arrays returns compile-time constants

Stats

• 3,886 tests passing
• 81.5% branch coverage
• 430 MC integration tests

Links

• Documentation
• Playground
• GitHub
• Changelog