Crate runefix_core

runefix-core

Unicode-aware display width engine for terminals, TUI, and Markdown rendering.

runefix-core provides precise width computation for multilingual text, with support for:

• East Asian fullwidth characters (CJK)
• Emoji (including multi-codepoint ZWJ sequences)
• Fullwidth punctuation and symbol variants
• Grapheme-aware string truncation and wrapping

It ensures consistent text alignment across platforms and fonts by working at the grapheme cluster level, consulting curated Unicode-derived datasets.

Features

🧬 Atom API

• atoms – Runefix-specific visual segmentation for layout (width-based units)

🧩 Segmentation API

• graphemes – Unicode-compliant grapheme cluster splitting (UAX #29)

📏 Measurement API

• display_width – Total width of a string (grapheme-aware, terminal-style)
• display_widths – Widths of each grapheme cluster (Vec<usize>)
• grapheme_widths – Widths with original clusters (Vec<(&str, usize)>)

📐 Layout API

• truncate_by_width – Truncates text by width without splitting graphemes
• split_by_width – Wraps a string into lines based on terminal width

🍭 Ergonomic Extensions

• RuneDisplayWidth – Trait for:
  • .rune_width() on char
  • .width(), .display_width(), .display_widths() on str

Example

use runefix_core::{RuneDisplayWidth, grapheme_widths};

assert_eq!('你'.rune_width(), 2);
assert_eq!(
    grapheme_widths("Hi，世界"),
    vec![("H", 1), ("i", 1), ("，", 2), ("世", 2), ("界", 2)]
);

Resources

• 📖 Dataset source & CLI
• 📦 Crates.io
• 🧪 docs.rs Documentation

Note: Enable the policy feature to use configurable width strategies such as terminal(), markdown(), or compact().

Constants

UNICODE_VERSION

Unicode Version used by this build (auto-synced). auto-updated: 2025-05-27

Traits

RuneDisplayWidth

Extension trait for measuring the display width of runes, graphemes, and strings.

Functions

atoms

Splits the input string into layout atoms — visual units used for width-aware layout.

display_width

Returns the total display width (in columns) of a string, based on grapheme clusters.

display_widths

Returns the display width (in columns) of each grapheme cluster in the input string.

grapheme_widths

Returns the display width of each grapheme cluster in the input string.

graphemes

Returns all Unicode grapheme clusters in the input string, following UAX #29.

split_by_width

Splits a string into lines based on display width, preserving grapheme boundaries.

truncate_by_width

Truncates a string by display width while preserving grapheme cluster boundaries.