| 'use strict'; |
| var numberIsNan = require('number-is-nan'); |
| |
| module.exports = function (x) { |
| if (numberIsNan(x)) { |
| return false; |
| } |
| |
| // https://github.com/nodejs/io.js/blob/cff7300a578be1b10001f2d967aaedc88aee6402/lib/readline.js#L1369 |
| |
| // code points are derived from: |
| // http://www.unix.org/Public/UNIDATA/EastAsianWidth.txt |
| if (x >= 0x1100 && ( |
| x <= 0x115f || // Hangul Jamo |
| 0x2329 === x || // LEFT-POINTING ANGLE BRACKET |
| 0x232a === x || // RIGHT-POINTING ANGLE BRACKET |
| // CJK Radicals Supplement .. Enclosed CJK Letters and Months |
| (0x2e80 <= x && x <= 0x3247 && x !== 0x303f) || |
| // Enclosed CJK Letters and Months .. CJK Unified Ideographs Extension A |
| 0x3250 <= x && x <= 0x4dbf || |
| // CJK Unified Ideographs .. Yi Radicals |
| 0x4e00 <= x && x <= 0xa4c6 || |
| // Hangul Jamo Extended-A |
| 0xa960 <= x && x <= 0xa97c || |
| // Hangul Syllables |
| 0xac00 <= x && x <= 0xd7a3 || |
| // CJK Compatibility Ideographs |
| 0xf900 <= x && x <= 0xfaff || |
| // Vertical Forms |
| 0xfe10 <= x && x <= 0xfe19 || |
| // CJK Compatibility Forms .. Small Form Variants |
| 0xfe30 <= x && x <= 0xfe6b || |
| // Halfwidth and Fullwidth Forms |
| 0xff01 <= x && x <= 0xff60 || |
| 0xffe0 <= x && x <= 0xffe6 || |
| // Kana Supplement |
| 0x1b000 <= x && x <= 0x1b001 || |
| // Enclosed Ideographic Supplement |
| 0x1f200 <= x && x <= 0x1f251 || |
| // CJK Unified Ideographs Extension B .. Tertiary Ideographic Plane |
| 0x20000 <= x && x <= 0x3fffd)) { |
| return true; |
| } |
| |
| return false; |
| } |
