encoder.js
1.09 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = new Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
function _toArray(arr) { return Array.isArray(arr) ? arr : Array.from(arr); }
function con(n) {
return 0x80 | n & 0x3f;
}
export function encode(str) {
var arr = str.split("").map(function (x) {
return x.charCodeAt(0);
});
return _encode(arr);
}
function _encode(arr) {
if (arr.length === 0) {
return [];
}
var _arr = _toArray(arr),
n = _arr[0],
ns = _arr.slice(1);
if (n < 0) {
throw new Error("utf8");
}
if (n < 0x80) {
return [n].concat(_toConsumableArray(_encode(ns)));
}
if (n < 0x800) {
return [0xc0 | n >>> 6, con(n)].concat(_toConsumableArray(_encode(ns)));
}
if (n < 0x10000) {
return [0xe0 | n >>> 12, con(n >>> 6), con(n)].concat(_toConsumableArray(_encode(ns)));
}
if (n < 0x110000) {
return [0xf0 | n >>> 18, con(n >>> 12), con(n >>> 6), con(n)].concat(_toConsumableArray(_encode(ns)));
}
throw new Error("utf8");
}