You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
56 lines
1.5 KiB
JavaScript
56 lines
1.5 KiB
JavaScript
// imported from https://github.com/unshiftio/yeast
|
|
"use strict";
|
|
Object.defineProperty(exports, "__esModule", { value: true });
|
|
exports.yeast = exports.decode = exports.encode = void 0;
|
|
const alphabet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-_".split(""), length = 64, map = {};
|
|
let seed = 0, i = 0, prev;
|
|
/**
|
|
* Return a string representing the specified number.
|
|
*
|
|
* @param {Number} num The number to convert.
|
|
* @returns {String} The string representation of the number.
|
|
* @api public
|
|
*/
|
|
function encode(num) {
|
|
let encoded = "";
|
|
do {
|
|
encoded = alphabet[num % length] + encoded;
|
|
num = Math.floor(num / length);
|
|
} while (num > 0);
|
|
return encoded;
|
|
}
|
|
exports.encode = encode;
|
|
/**
|
|
* Return the integer value specified by the given string.
|
|
*
|
|
* @param {String} str The string to convert.
|
|
* @returns {Number} The integer value represented by the string.
|
|
* @api public
|
|
*/
|
|
function decode(str) {
|
|
let decoded = 0;
|
|
for (i = 0; i < str.length; i++) {
|
|
decoded = decoded * length + map[str.charAt(i)];
|
|
}
|
|
return decoded;
|
|
}
|
|
exports.decode = decode;
|
|
/**
|
|
* Yeast: A tiny growing id generator.
|
|
*
|
|
* @returns {String} A unique id.
|
|
* @api public
|
|
*/
|
|
function yeast() {
|
|
const now = encode(+new Date());
|
|
if (now !== prev)
|
|
return (seed = 0), (prev = now);
|
|
return now + "." + encode(seed++);
|
|
}
|
|
exports.yeast = yeast;
|
|
//
|
|
// Map each character to its index.
|
|
//
|
|
for (; i < length; i++)
|
|
map[alphabet[i]] = i;
|