Text width

Terminal layout uses display cells, not UTF-8 bytes, Unicode scalar values, or Rust string length. Urushi segments text into grapheme clusters and keeps each cluster atomic during wrapping and clipping.

See width-sensitive behavior

8 cells
日本語
status

Grapheme-safe wrapping CJK, combining sequences, and emoji stay atomic at line edges.

a→      b
12345678
next row

Tabs and finite width Configure tab stops and wrap against terminal-cell columns.

Run the complete Text width quickstart ↓

Quickstart

cargo new width-demo
cd width-demo
cargo add urushi

Replace src/main.rs with:

use std::error::Error;

use urushi::{
    Available, PrintableText, RenderSettings, TextStyle, View, render, resolve,
};

fn main() -> Result<(), Box<dyn Error>> {
    assert_eq!(PrintableText::new("日本語").width(), 6);

    let view = View::text("日本語 status", TextStyle::new());
    let resolved = resolve(&view, Available::columns(8))?;
    print!("{}", render(&resolved, &RenderSettings::default()));
    Ok(())
}

Run it with cargo run:

Rendered at eight columns

日本語
status

The three Japanese graphemes occupy six cells. Wrapping keeps every grapheme whole and removes the break-space before status.

How terminal width works

One visible grapheme may contain several Unicode scalar values and occupy zero, one, or two terminal cells. This affects CJK text, combining marks, and emoji sequences.

Urushi applies one width model to wrapping, alignment, grids, padding, borders, dimensions, Canvas clipping, and Ratatui target rectangles. A wide grapheme is never split between rows or left as a half-cell at an edge.

str::len() counts bytes. Do not use it as a cursor column unless the input is known to be ASCII. Use Urushi’s printable text and grapheme types for terminal measurement.

Raw ANSI and cursor controls are not text. They break measurement and are rejected by plain-text constructors. Express appearance through Styles and terminal actions through the appropriate terminal API.

Continue by task

• Configure tabs and wrapping
• Look up the complete Text width API