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faster wcwidth with lookup table #798

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Jul 18, 2017
Merged

faster wcwidth with lookup table #798

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b965d0a
faster wcwidth with lookup table
jerch Jul 16, 2017
dd0fcb6
fixing whitespaces
jerch Jul 16, 2017
1722248
fixing whitespaces
jerch Jul 16, 2017
ba2d0e8
fixing whitespaces
jerch Jul 16, 2017
6733c6c
test speedup defensive
jerch Jul 16, 2017
5d87b54
test speedup defensive
jerch Jul 16, 2017
1232c00
some fixes
jerch Jul 16, 2017
6ed5c9e
speed test commented out
jerch Jul 16, 2017
598a729
fixes #799 - lookup table is created on first wcwidth call for char >…
jerch Jul 17, 2017
20048d3
Merge branch 'master' into faster_wcwidth
Tyriar Jul 17, 2017
cd5827e
higher timeout for test case
jerch Jul 18, 2017
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137 changes: 137 additions & 0 deletions src/InputHandler.test.ts
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Original file line number Diff line number Diff line change
@@ -1,5 +1,6 @@
import { assert } from 'chai';
import { InputHandler } from './InputHandler';
import { wcwidth } from './InputHandler';

describe('InputHandler', () => {
describe('setCursorStyle', () => {
Expand Down Expand Up @@ -47,3 +48,139 @@ describe('InputHandler', () => {
});
});
});

const old_wcwidth = (function(opts) {
// extracted from https://www.cl.cam.ac.uk/%7Emgk25/ucs/wcwidth.c
// combining characters
const COMBINING = [
[0x0300, 0x036F], [0x0483, 0x0486], [0x0488, 0x0489],
[0x0591, 0x05BD], [0x05BF, 0x05BF], [0x05C1, 0x05C2],
[0x05C4, 0x05C5], [0x05C7, 0x05C7], [0x0600, 0x0603],
[0x0610, 0x0615], [0x064B, 0x065E], [0x0670, 0x0670],
[0x06D6, 0x06E4], [0x06E7, 0x06E8], [0x06EA, 0x06ED],
[0x070F, 0x070F], [0x0711, 0x0711], [0x0730, 0x074A],
[0x07A6, 0x07B0], [0x07EB, 0x07F3], [0x0901, 0x0902],
[0x093C, 0x093C], [0x0941, 0x0948], [0x094D, 0x094D],
[0x0951, 0x0954], [0x0962, 0x0963], [0x0981, 0x0981],
[0x09BC, 0x09BC], [0x09C1, 0x09C4], [0x09CD, 0x09CD],
[0x09E2, 0x09E3], [0x0A01, 0x0A02], [0x0A3C, 0x0A3C],
[0x0A41, 0x0A42], [0x0A47, 0x0A48], [0x0A4B, 0x0A4D],
[0x0A70, 0x0A71], [0x0A81, 0x0A82], [0x0ABC, 0x0ABC],
[0x0AC1, 0x0AC5], [0x0AC7, 0x0AC8], [0x0ACD, 0x0ACD],
[0x0AE2, 0x0AE3], [0x0B01, 0x0B01], [0x0B3C, 0x0B3C],
[0x0B3F, 0x0B3F], [0x0B41, 0x0B43], [0x0B4D, 0x0B4D],
[0x0B56, 0x0B56], [0x0B82, 0x0B82], [0x0BC0, 0x0BC0],
[0x0BCD, 0x0BCD], [0x0C3E, 0x0C40], [0x0C46, 0x0C48],
[0x0C4A, 0x0C4D], [0x0C55, 0x0C56], [0x0CBC, 0x0CBC],
[0x0CBF, 0x0CBF], [0x0CC6, 0x0CC6], [0x0CCC, 0x0CCD],
[0x0CE2, 0x0CE3], [0x0D41, 0x0D43], [0x0D4D, 0x0D4D],
[0x0DCA, 0x0DCA], [0x0DD2, 0x0DD4], [0x0DD6, 0x0DD6],
[0x0E31, 0x0E31], [0x0E34, 0x0E3A], [0x0E47, 0x0E4E],
[0x0EB1, 0x0EB1], [0x0EB4, 0x0EB9], [0x0EBB, 0x0EBC],
[0x0EC8, 0x0ECD], [0x0F18, 0x0F19], [0x0F35, 0x0F35],
[0x0F37, 0x0F37], [0x0F39, 0x0F39], [0x0F71, 0x0F7E],
[0x0F80, 0x0F84], [0x0F86, 0x0F87], [0x0F90, 0x0F97],
[0x0F99, 0x0FBC], [0x0FC6, 0x0FC6], [0x102D, 0x1030],
[0x1032, 0x1032], [0x1036, 0x1037], [0x1039, 0x1039],
[0x1058, 0x1059], [0x1160, 0x11FF], [0x135F, 0x135F],
[0x1712, 0x1714], [0x1732, 0x1734], [0x1752, 0x1753],
[0x1772, 0x1773], [0x17B4, 0x17B5], [0x17B7, 0x17BD],
[0x17C6, 0x17C6], [0x17C9, 0x17D3], [0x17DD, 0x17DD],
[0x180B, 0x180D], [0x18A9, 0x18A9], [0x1920, 0x1922],
[0x1927, 0x1928], [0x1932, 0x1932], [0x1939, 0x193B],
[0x1A17, 0x1A18], [0x1B00, 0x1B03], [0x1B34, 0x1B34],
[0x1B36, 0x1B3A], [0x1B3C, 0x1B3C], [0x1B42, 0x1B42],
[0x1B6B, 0x1B73], [0x1DC0, 0x1DCA], [0x1DFE, 0x1DFF],
[0x200B, 0x200F], [0x202A, 0x202E], [0x2060, 0x2063],
[0x206A, 0x206F], [0x20D0, 0x20EF], [0x302A, 0x302F],
[0x3099, 0x309A], [0xA806, 0xA806], [0xA80B, 0xA80B],
[0xA825, 0xA826], [0xFB1E, 0xFB1E], [0xFE00, 0xFE0F],
[0xFE20, 0xFE23], [0xFEFF, 0xFEFF], [0xFFF9, 0xFFFB],
[0x10A01, 0x10A03], [0x10A05, 0x10A06], [0x10A0C, 0x10A0F],
[0x10A38, 0x10A3A], [0x10A3F, 0x10A3F], [0x1D167, 0x1D169],
[0x1D173, 0x1D182], [0x1D185, 0x1D18B], [0x1D1AA, 0x1D1AD],
[0x1D242, 0x1D244], [0xE0001, 0xE0001], [0xE0020, 0xE007F],
[0xE0100, 0xE01EF]
];
// binary search
function bisearch(ucs) {
let min = 0;
let max = COMBINING.length - 1;
let mid;
if (ucs < COMBINING[0][0] || ucs > COMBINING[max][1])
return false;
while (max >= min) {
mid = Math.floor((min + max) / 2);
if (ucs > COMBINING[mid][1])
min = mid + 1;
else if (ucs < COMBINING[mid][0])
max = mid - 1;
else
return true;
}
return false;
}
function wcwidth(ucs) {
// test for 8-bit control characters
if (ucs === 0)
return opts.nul;
if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0))
return opts.control;
// binary search in table of non-spacing characters
if (bisearch(ucs))
return 0;
// if we arrive here, ucs is not a combining or C0/C1 control character
if (isWide(ucs)) {
return 2;
}
return 1;
}
function isWide(ucs) {
return (
ucs >= 0x1100 && (
ucs <= 0x115f || // Hangul Jamo init. consonants
ucs === 0x2329 ||
ucs === 0x232a ||
(ucs >= 0x2e80 && ucs <= 0xa4cf && ucs !== 0x303f) || // CJK..Yi
(ucs >= 0xac00 && ucs <= 0xd7a3) || // Hangul Syllables
(ucs >= 0xf900 && ucs <= 0xfaff) || // CJK Compat Ideographs
(ucs >= 0xfe10 && ucs <= 0xfe19) || // Vertical forms
(ucs >= 0xfe30 && ucs <= 0xfe6f) || // CJK Compat Forms
(ucs >= 0xff00 && ucs <= 0xff60) || // Fullwidth Forms
(ucs >= 0xffe0 && ucs <= 0xffe6) ||
(ucs >= 0x20000 && ucs <= 0x2fffd) ||
(ucs >= 0x30000 && ucs <= 0x3fffd)));
}
return wcwidth;
})({nul: 0, control: 0}); // configurable options

describe('wcwidth', () => {
it('same as old implementation for BMP and individual higher', (done) => {
for (let i = 0; i < 65536; ++i)
assert.equal(wcwidth(i), old_wcwidth(i));
// test some individual higher to fullfill branching
assert.equal(wcwidth(0x10A01), old_wcwidth(0x10A01));
assert.equal(wcwidth(0x30000), old_wcwidth(0x30000));
assert.equal(wcwidth(0x3fffe), old_wcwidth(0x3fffe));
done();
}).timeout(3000);
/*
it('new is at least 5 times faster', () => {
let start_new = new Date().getTime();
let x = 0;
for (let runs = 0; runs < 1; ++runs)
for (let i = 0; i < 65536; ++i)
x = wcwidth(i);
let end_new = new Date().getTime();
let start_old = new Date().getTime();
let y = 0;
for (let runs = 0; runs < 1; ++runs)
for (let i = 0; i < 65536; ++i)
y = old_wcwidth(i);
let end_old = new Date().getTime();
// console.log((end_new - start_new));
// console.log((end_old - start_old));
assert.equal(((end_new - start_new) * 5 < (end_old - start_old)), true);
});
*/
});
238 changes: 145 additions & 93 deletions src/InputHandler.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1462,95 +1462,97 @@ export class InputHandler implements IInputHandler {
}
}

const wcwidth = (function(opts) {
// extracted from https://www.cl.cam.ac.uk/%7Emgk25/ucs/wcwidth.c
// combining characters
const COMBINING = [
[0x0300, 0x036F], [0x0483, 0x0486], [0x0488, 0x0489],
[0x0591, 0x05BD], [0x05BF, 0x05BF], [0x05C1, 0x05C2],
[0x05C4, 0x05C5], [0x05C7, 0x05C7], [0x0600, 0x0603],
[0x0610, 0x0615], [0x064B, 0x065E], [0x0670, 0x0670],
[0x06D6, 0x06E4], [0x06E7, 0x06E8], [0x06EA, 0x06ED],
[0x070F, 0x070F], [0x0711, 0x0711], [0x0730, 0x074A],
[0x07A6, 0x07B0], [0x07EB, 0x07F3], [0x0901, 0x0902],
[0x093C, 0x093C], [0x0941, 0x0948], [0x094D, 0x094D],
[0x0951, 0x0954], [0x0962, 0x0963], [0x0981, 0x0981],
[0x09BC, 0x09BC], [0x09C1, 0x09C4], [0x09CD, 0x09CD],
[0x09E2, 0x09E3], [0x0A01, 0x0A02], [0x0A3C, 0x0A3C],
[0x0A41, 0x0A42], [0x0A47, 0x0A48], [0x0A4B, 0x0A4D],
[0x0A70, 0x0A71], [0x0A81, 0x0A82], [0x0ABC, 0x0ABC],
[0x0AC1, 0x0AC5], [0x0AC7, 0x0AC8], [0x0ACD, 0x0ACD],
[0x0AE2, 0x0AE3], [0x0B01, 0x0B01], [0x0B3C, 0x0B3C],
[0x0B3F, 0x0B3F], [0x0B41, 0x0B43], [0x0B4D, 0x0B4D],
[0x0B56, 0x0B56], [0x0B82, 0x0B82], [0x0BC0, 0x0BC0],
[0x0BCD, 0x0BCD], [0x0C3E, 0x0C40], [0x0C46, 0x0C48],
[0x0C4A, 0x0C4D], [0x0C55, 0x0C56], [0x0CBC, 0x0CBC],
[0x0CBF, 0x0CBF], [0x0CC6, 0x0CC6], [0x0CCC, 0x0CCD],
[0x0CE2, 0x0CE3], [0x0D41, 0x0D43], [0x0D4D, 0x0D4D],
[0x0DCA, 0x0DCA], [0x0DD2, 0x0DD4], [0x0DD6, 0x0DD6],
[0x0E31, 0x0E31], [0x0E34, 0x0E3A], [0x0E47, 0x0E4E],
[0x0EB1, 0x0EB1], [0x0EB4, 0x0EB9], [0x0EBB, 0x0EBC],
[0x0EC8, 0x0ECD], [0x0F18, 0x0F19], [0x0F35, 0x0F35],
[0x0F37, 0x0F37], [0x0F39, 0x0F39], [0x0F71, 0x0F7E],
[0x0F80, 0x0F84], [0x0F86, 0x0F87], [0x0F90, 0x0F97],
[0x0F99, 0x0FBC], [0x0FC6, 0x0FC6], [0x102D, 0x1030],
[0x1032, 0x1032], [0x1036, 0x1037], [0x1039, 0x1039],
[0x1058, 0x1059], [0x1160, 0x11FF], [0x135F, 0x135F],
[0x1712, 0x1714], [0x1732, 0x1734], [0x1752, 0x1753],
[0x1772, 0x1773], [0x17B4, 0x17B5], [0x17B7, 0x17BD],
[0x17C6, 0x17C6], [0x17C9, 0x17D3], [0x17DD, 0x17DD],
[0x180B, 0x180D], [0x18A9, 0x18A9], [0x1920, 0x1922],
[0x1927, 0x1928], [0x1932, 0x1932], [0x1939, 0x193B],
[0x1A17, 0x1A18], [0x1B00, 0x1B03], [0x1B34, 0x1B34],
[0x1B36, 0x1B3A], [0x1B3C, 0x1B3C], [0x1B42, 0x1B42],
[0x1B6B, 0x1B73], [0x1DC0, 0x1DCA], [0x1DFE, 0x1DFF],
[0x200B, 0x200F], [0x202A, 0x202E], [0x2060, 0x2063],
[0x206A, 0x206F], [0x20D0, 0x20EF], [0x302A, 0x302F],
[0x3099, 0x309A], [0xA806, 0xA806], [0xA80B, 0xA80B],
[0xA825, 0xA826], [0xFB1E, 0xFB1E], [0xFE00, 0xFE0F],
[0xFE20, 0xFE23], [0xFEFF, 0xFEFF], [0xFFF9, 0xFFFB],
[0x10A01, 0x10A03], [0x10A05, 0x10A06], [0x10A0C, 0x10A0F],
[0x10A38, 0x10A3A], [0x10A3F, 0x10A3F], [0x1D167, 0x1D169],
[0x1D173, 0x1D182], [0x1D185, 0x1D18B], [0x1D1AA, 0x1D1AD],
[0x1D242, 0x1D244], [0xE0001, 0xE0001], [0xE0020, 0xE007F],
[0xE0100, 0xE01EF]
];
// binary search
function bisearch(ucs) {
let min = 0;
let max = COMBINING.length - 1;
let mid;
if (ucs < COMBINING[0][0] || ucs > COMBINING[max][1])
export const wcwidth = (function(opts) {
// extracted from https://www.cl.cam.ac.uk/%7Emgk25/ucs/wcwidth.c
// combining characters
const COMBINING_BMP = [
[0x0300, 0x036F], [0x0483, 0x0486], [0x0488, 0x0489],
[0x0591, 0x05BD], [0x05BF, 0x05BF], [0x05C1, 0x05C2],
[0x05C4, 0x05C5], [0x05C7, 0x05C7], [0x0600, 0x0603],
[0x0610, 0x0615], [0x064B, 0x065E], [0x0670, 0x0670],
[0x06D6, 0x06E4], [0x06E7, 0x06E8], [0x06EA, 0x06ED],
[0x070F, 0x070F], [0x0711, 0x0711], [0x0730, 0x074A],
[0x07A6, 0x07B0], [0x07EB, 0x07F3], [0x0901, 0x0902],
[0x093C, 0x093C], [0x0941, 0x0948], [0x094D, 0x094D],
[0x0951, 0x0954], [0x0962, 0x0963], [0x0981, 0x0981],
[0x09BC, 0x09BC], [0x09C1, 0x09C4], [0x09CD, 0x09CD],
[0x09E2, 0x09E3], [0x0A01, 0x0A02], [0x0A3C, 0x0A3C],
[0x0A41, 0x0A42], [0x0A47, 0x0A48], [0x0A4B, 0x0A4D],
[0x0A70, 0x0A71], [0x0A81, 0x0A82], [0x0ABC, 0x0ABC],
[0x0AC1, 0x0AC5], [0x0AC7, 0x0AC8], [0x0ACD, 0x0ACD],
[0x0AE2, 0x0AE3], [0x0B01, 0x0B01], [0x0B3C, 0x0B3C],
[0x0B3F, 0x0B3F], [0x0B41, 0x0B43], [0x0B4D, 0x0B4D],
[0x0B56, 0x0B56], [0x0B82, 0x0B82], [0x0BC0, 0x0BC0],
[0x0BCD, 0x0BCD], [0x0C3E, 0x0C40], [0x0C46, 0x0C48],
[0x0C4A, 0x0C4D], [0x0C55, 0x0C56], [0x0CBC, 0x0CBC],
[0x0CBF, 0x0CBF], [0x0CC6, 0x0CC6], [0x0CCC, 0x0CCD],
[0x0CE2, 0x0CE3], [0x0D41, 0x0D43], [0x0D4D, 0x0D4D],
[0x0DCA, 0x0DCA], [0x0DD2, 0x0DD4], [0x0DD6, 0x0DD6],
[0x0E31, 0x0E31], [0x0E34, 0x0E3A], [0x0E47, 0x0E4E],
[0x0EB1, 0x0EB1], [0x0EB4, 0x0EB9], [0x0EBB, 0x0EBC],
[0x0EC8, 0x0ECD], [0x0F18, 0x0F19], [0x0F35, 0x0F35],
[0x0F37, 0x0F37], [0x0F39, 0x0F39], [0x0F71, 0x0F7E],
[0x0F80, 0x0F84], [0x0F86, 0x0F87], [0x0F90, 0x0F97],
[0x0F99, 0x0FBC], [0x0FC6, 0x0FC6], [0x102D, 0x1030],
[0x1032, 0x1032], [0x1036, 0x1037], [0x1039, 0x1039],
[0x1058, 0x1059], [0x1160, 0x11FF], [0x135F, 0x135F],
[0x1712, 0x1714], [0x1732, 0x1734], [0x1752, 0x1753],
[0x1772, 0x1773], [0x17B4, 0x17B5], [0x17B7, 0x17BD],
[0x17C6, 0x17C6], [0x17C9, 0x17D3], [0x17DD, 0x17DD],
[0x180B, 0x180D], [0x18A9, 0x18A9], [0x1920, 0x1922],
[0x1927, 0x1928], [0x1932, 0x1932], [0x1939, 0x193B],
[0x1A17, 0x1A18], [0x1B00, 0x1B03], [0x1B34, 0x1B34],
[0x1B36, 0x1B3A], [0x1B3C, 0x1B3C], [0x1B42, 0x1B42],
[0x1B6B, 0x1B73], [0x1DC0, 0x1DCA], [0x1DFE, 0x1DFF],
[0x200B, 0x200F], [0x202A, 0x202E], [0x2060, 0x2063],
[0x206A, 0x206F], [0x20D0, 0x20EF], [0x302A, 0x302F],
[0x3099, 0x309A], [0xA806, 0xA806], [0xA80B, 0xA80B],
[0xA825, 0xA826], [0xFB1E, 0xFB1E], [0xFE00, 0xFE0F],
[0xFE20, 0xFE23], [0xFEFF, 0xFEFF], [0xFFF9, 0xFFFB],
];
const COMBINING_HIGH = [
[0x10A01, 0x10A03], [0x10A05, 0x10A06], [0x10A0C, 0x10A0F],
[0x10A38, 0x10A3A], [0x10A3F, 0x10A3F], [0x1D167, 0x1D169],
[0x1D173, 0x1D182], [0x1D185, 0x1D18B], [0x1D1AA, 0x1D1AD],
[0x1D242, 0x1D244], [0xE0001, 0xE0001], [0xE0020, 0xE007F],
[0xE0100, 0xE01EF]
];
// binary search
function bisearch(ucs, data) {
let min = 0;
let max = data.length - 1;
let mid;
if (ucs < data[0][0] || ucs > data[max][1])
return false;
while (max >= min) {
mid = (min + max) >> 1;
if (ucs > data[mid][1])
min = mid + 1;
else if (ucs < data[mid][0])
max = mid - 1;
else
return true;
}
return false;
while (max >= min) {
mid = Math.floor((min + max) / 2);
if (ucs > COMBINING[mid][1])
min = mid + 1;
else if (ucs < COMBINING[mid][0])
max = mid - 1;
else
return true;
}
return false;
}
function wcwidth(ucs) {
// test for 8-bit control characters
if (ucs === 0)
return opts.nul;
if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0))
return opts.control;
// binary search in table of non-spacing characters
if (bisearch(ucs))
return 0;
// if we arrive here, ucs is not a combining or C0/C1 control character
if (isWide(ucs)) {
return 2;
}
return 1;
}
function isWide(ucs) {
return (
ucs >= 0x1100 && (
}
function wcwidthBMP(ucs) {
// test for 8-bit control characters
if (ucs === 0)
return opts.nul;
if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0))
return opts.control;
// binary search in table of non-spacing characters
if (bisearch(ucs, COMBINING_BMP))
return 0;
// if we arrive here, ucs is not a combining or C0/C1 control character
if (isWideBMP(ucs)) {
return 2;
}
return 1;
}
function isWideBMP(ucs) {
return (
ucs >= 0x1100 && (
ucs <= 0x115f || // Hangul Jamo init. consonants
ucs === 0x2329 ||
ucs === 0x232a ||
Expand All @@ -1560,9 +1562,59 @@ const wcwidth = (function(opts) {
(ucs >= 0xfe10 && ucs <= 0xfe19) || // Vertical forms
(ucs >= 0xfe30 && ucs <= 0xfe6f) || // CJK Compat Forms
(ucs >= 0xff00 && ucs <= 0xff60) || // Fullwidth Forms
(ucs >= 0xffe0 && ucs <= 0xffe6) ||
(ucs >= 0x20000 && ucs <= 0x2fffd) ||
(ucs >= 0x30000 && ucs <= 0x3fffd)));
}
return wcwidth;
(ucs >= 0xffe0 && ucs <= 0xffe6)));
}
function wcwidthHigh(ucs) {
if (bisearch(ucs, COMBINING_HIGH))
return 0;
if ((ucs >= 0x20000 && ucs <= 0x2fffd) || (ucs >= 0x30000 && ucs <= 0x3fffd)) {
return 2;
}
return 1;
}
const control = opts.control | 0;
let table = null;
function init_table() {
// lookup table for BMP
const CODEPOINTS = 65536; // BMP holds 65536 codepoints
const BITWIDTH = 2; // a codepoint can have a width of 0, 1 or 2
const ITEMSIZE = 32; // using uint32_t
const CONTAINERSIZE = CODEPOINTS * BITWIDTH / ITEMSIZE;
const CODEPOINTS_PER_ITEM = ITEMSIZE / BITWIDTH;
table = (typeof Uint32Array === 'undefined')
? new Array(CONTAINERSIZE)
: new Uint32Array(CONTAINERSIZE);
for (let i = 0; i < CONTAINERSIZE; ++i) {
let num = 0;
let pos = CODEPOINTS_PER_ITEM;
while (pos--)
num = (num << 2) | wcwidthBMP(CODEPOINTS_PER_ITEM * i + pos);
table[i] = num;
}
return table;
}
// get width from lookup table
// position in container : num / CODEPOINTS_PER_ITEM
// ==> n = table[Math.floor(num / 16)]
// ==> n = table[num >> 4]
// 16 codepoints per number: FFEEDDCCBBAA99887766554433221100
// position in number : (num % CODEPOINTS_PER_ITEM) * BITWIDTH
// ==> m = (n % 16) * 2
// ==> m = (num & 15) << 1
// right shift to position m
// ==> n = n >> m e.g. m=12 000000000000FFEEDDCCBBAA99887766
// we are only interested in 2 LSBs, cut off higher bits
// ==> n = n & 3 e.g. 000000000000000000000000000000XX
return function (num) {
num = num | 0; // get asm.js like optimization under V8
if (num < 32)
return control | 0;
if (num < 127)
return 1;
let t = table || init_table();
if (num < 65536)
return t[num >> 4] >> ((num & 15) << 1) & 3;
// do a full search for high codepoints
return wcwidthHigh(num);
};
})({nul: 0, control: 0}); // configurable options