runefix-core

🎯 A Rust core library that fixes terminal and Markdown misalignment caused by CJK and emoji widths.

✨ Overview

runefix-core is a Unicode-based display width engine that provides precise character width calculation, designed for:

Terminal CLI alignment
Markdown table rendering
TUI layout engines
Rich text editor rendering

Its goal is to solve a decades-long problem: misaligned characters in terminal and UI environments due to inconsistent Unicode width handling. This includes:

CJK characters (Chinese, Japanese, Korean), Kana, and Hangul syllables
Emoji (base, composite, and flag sequences)
Fullwidth punctuation and multilingual symbols
Grapheme cluster boundary cases

✅ Key Features

✅ Accurate width detection for emoji, CJK, Hangul, Kana, and fullwidth symbols
✅ Full support for grapheme clusters (emoji composition, regional indicators)
✅ Zero dependencies, minimal API, compatible with any terminal or UI renderer
✅ Fully reproducible datasets, powered by char-table
✅ Language bindings planned for JS / Python / Go and more

🚀 Quick Example

use runefix_core::RuneDisplayWidth;

fn main() {
    println!("{}", "你".rune_width());           // Output: 2
    println!("{}", "😂".rune_width());           // Output: 2
    println!("{}", "你a1👇".rune_width_total()); // Output: 6
}

📷 Real-World Examples

For a full demo of grapheme-aware alignment and terminal behavior, see examples/text_align.rs.

It showcases:

Naive centering using .chars().count() ❌
Fixed centering using runefix_core::RuneDisplayWidth ✅
Screenshot comparisons across terminals

👉 Read more in examples/README.md

📦 Installation

Add the following to your Cargo.toml:

# Stable release (recommended)
runefix-core = "0.1"

See crates.io for the latest version.

📚 Use Cases

🖥️ Terminal alignment (CLI box drawing, tables)
🧾 Markdown renderers (accurate width handling in table cells)
📊 TUI layout engines (React-style terminal UIs)
📄 Editors and terminal emulators (accurate text wrapping)
🧩 Width testing tools, playgrounds, and visualization platforms

📁 Dataset Sources

This crate relies on structured, versioned datasets from char-table, including:

emoji_base.json, emoji_zwj.json
cjk_unified.json, japanese_kana.json, korean_syllables.json
fullwidth_variants.json, fullwidth_punctuations.json

All datasets are reproducible, regularly updated, and aligned with the latest Unicode releases.

🛠️ Project Status

Module	Status
CJK width detection	✅ Completed
Emoji width support	✅ Completed
Grapheme cluster	✅ Completed

📌 CHANGELOG

See CHANGELOG.md for version history.

🔖 License

📣 Project Affiliation

This project is maintained by the runefix-labs organization. It serves as the core engine for the runefix suite — a multi-language, cross-platform solution for Unicode width handling.

🌐 Contact

GitHub: github.com/runefix-labs
Author: pokeyaro
Email: pokeya.mystic@gmail.com

runefix-core 0.1.0