21 lines
507 B
JavaScript
21 lines
507 B
JavaScript
/*!
|
|
* is-number <https://github.com/jonschlinkert/is-number>
|
|
*
|
|
* Copyright (c) 2014-2017, Jon Schlinkert.
|
|
* Released under the MIT License.
|
|
*/
|
|
|
|
'use strict';
|
|
|
|
module.exports = function isNumber(num) {
|
|
var type = typeof num;
|
|
|
|
if (type === 'string' || num instanceof String) {
|
|
// an empty string would be coerced to true with the below logic
|
|
if (!num.trim()) return false;
|
|
} else if (type !== 'number' && !(num instanceof Number)) {
|
|
return false;
|
|
}
|
|
|
|
return (num - num + 1) >= 0;
|
|
};
|