| 'use strict'; |
| /* eslint-disable yoda */ |
| module.exports = x => { |
| if (Number.isNaN(x)) { |
| return false; |
| } |
| |
| // code points are derived from: |
| // http://www.unix.org/Public/UNIDATA/EastAsianWidth.txt |
| if ( |
| x >= 0x1100 && ( |
| x <= 0x115f || // Hangul Jamo |
| x === 0x2329 || // LEFT-POINTING ANGLE BRACKET |
| x === 0x232a || // 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; |
| }; |