aaac7fed
 liuqimichale
add
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/*!
* repeat-string <https://github.com/jonschlinkert/repeat-string>
*
* Copyright (c) 2014-2015, Jon Schlinkert.
* Licensed under the MIT License.
*/
'use strict';
/**
* Results cache
*/
var res = '';
var cache;
/**
* Expose `repeat`
*/
module.exports = repeat;
/**
* Repeat the given `string` the specified `number`
* of times.
*
* **Example:**
*
* ```js
* var repeat = require('repeat-string');
* repeat('A', 5);
* //=> AAAAA
* ```
*
* @param {String} `string` The string to repeat
* @param {Number} `number` The number of times to repeat the string
* @return {String} Repeated string
* @api public
*/
function repeat(str, num) {
if (typeof str !== 'string') {
throw new TypeError('expected a string');
}
// cover common, quick use cases
if (num === 1) return str;
if (num === 2) return str + str;
var max = str.length * num;
if (cache !== str || typeof cache === 'undefined') {
cache = str;
res = '';
} else if (res.length >= max) {
return res.substr(0, max);
}
while (max > res.length && num > 1) {
if (num & 1) {
res += str;
}
num >>= 1;
str += str;
}
res += str;
res = res.substr(0, max);
return res;
}
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