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| function con(n) {
| return 0x80 | (n & 0x3f);
| }
|
| export function encode(str) {
| const arr = str.split("").map(x => x.charCodeAt(0));
| return _encode(arr);
| }
|
| function _encode(arr) {
| if (arr.length === 0) {
| return [];
| }
|
| const [n, ...ns] = arr;
|
| if (n < 0) {
| throw new Error("utf8");
| }
|
| if (n < 0x80) {
| return [n, ..._encode(ns)];
| }
|
| if (n < 0x800) {
| return [0xc0 | (n >>> 6), con(n), ..._encode(ns)];
| }
|
| if (n < 0x10000) {
| return [0xe0 | (n >>> 12), con(n >>> 6), con(n), ..._encode(ns)];
| }
|
| if (n < 0x110000) {
| return [
| 0xf0 | (n >>> 18),
| con(n >>> 12),
| con(n >>> 6),
| con(n),
| ..._encode(ns)
| ];
| }
|
| throw new Error("utf8");
| }
|
|
