47 lines
1.4 KiB
JavaScript
47 lines
1.4 KiB
JavaScript
|
'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;
|
||
|
|
}
|