Function unicodeWidth

unicodeWidth(str): number

Calculate the physical width of a string in a TTY-like environment. This is useful for cases such as calculating where a line-wrap will occur and underlining strings.

The physical width is given by the number of columns required to display the string. The number of columns a given unicode character occupies can vary depending on the character itself.

Parameters

str: string
The string to measure.

Returns number

The unicode width of the string.

Example: Calculating the unicode width of a string

import { unicodeWidth } from "@std/cli/unicode-width";
import { assertEquals } from "@std/assert";

assertEquals(unicodeWidth("hello world"), 11);
assertEquals(unicodeWidth("天地玄黃宇宙洪荒"), 16);
assertEquals(unicodeWidth("ｆｕｌｌｗｉｄｔｈ"), 18);

Example: Calculating the unicode width of a color-encoded string

import { unicodeWidth } from "@std/cli/unicode-width";
import { stripAnsiCode } from "@std/fmt/colors";
import { assertEquals } from "@std/assert";

assertEquals(unicodeWidth(stripAnsiCode("\x1b[36mголубой\x1b[39m")), 7);
assertEquals(unicodeWidth(stripAnsiCode("\x1b[31m紅色\x1b[39m")), 4);
assertEquals(unicodeWidth(stripAnsiCode("\x1B]8;;https://deno.land\x07🦕\x1B]8;;\x07")), 2);

Use stripAnsiCode to remove ANSI escape codes from a string before passing it to unicodeWidth.