Unicode Width Approximation (WASM)

A library for calculating the display width of Unicode strings in terminal/monospace environments.

Installation

npm install unicode-width-approximation

Usage

import {
    getStringWidth,
    getCodepointWidth,
    isWideChar,
    isZeroWidth
} from "unicode-width-approximation";

// Get width of strings
console.log(getStringWidth("hello"));      // 5
console.log(getStringWidth("中文"));        // 4
console.log(getStringWidth("👨‍👩‍👧‍👦"));  // 2

// Get width of single code points
console.log(getCodepointWidth(0x41));    // 1 (ASCII 'A')
console.log(getCodepointWidth(0x4E00));  // 2 (CJK)
console.log(getCodepointWidth(0x1F600)); // 2 (emoji)

TypeScript

TypeScript type definitions are included.

import { getStringWidth, getCodepointWidth } from "unicode-width-approximation";

const width: number = getStringWidth("hello世界");
console.log(width);  // 9

API

getStringWidth(s: string): number

Calculate the total display width of a string.

getCodepointWidth(code: number): number

Get the display width of a single Unicode code point (0, 1, or 2).

isWideChar(code: number): boolean

Check if a code point is a wide character (East Asian Wide or Fullwidth).

isZeroWidth(code: number): boolean

Check if a code point is a zero-width character.

Building

Requires Emscripten to be installed.

npm run build

Testing

npm test

License

MIT License