📏 Calculates the visual width of a string in a terminal.

Syntax

import { stringWidth } from '@opentf/std';

stringWidth(str: string): number

Examples

stringWidth('abc') //=> 3
stringWidth('\x1b[31mabc\x1b[0m') //=> 3
stringWidth('🔥') //=> 2
stringWidth('こんにちは') //=> 10

Implementation Strategy

Unlike many other libraries that ship large internal Unicode lookup tables, this implementation uses a Platform-First approach:

1. Native Engine: Uses the native Intl.Segmenter (Baseline 2024) to accurately identify grapheme clusters.

2. Zero Bundle Bloat: Leverages the browser/runtime's built-in Unicode data, keeping the library size extremely small.

3. High Precision: Accurately handles complex sequences like ZWJ Emojis, Skin Tone Modifiers, and Regional Indicators (Flags) that simple regex-based approaches miss.

4. ANSI Awareness: Automatically strips ANSI escape codes (using a comprehensive ECMA-48 compliant regex) before calculating width.