flying-hero
96f6318101
新增: - backend/venv/ - Python 虚拟环境 - backend/start.sh - 启动脚本（使用虚拟环境） - backend/requirements.txt - 依赖列表 - .gitignore - 忽略虚拟环境和缓存文件 说明: - 每个项目使用独立虚拟环境 - 避免依赖冲突 - 启动脚本自动创建和激活虚拟环境
36 lines
802 B
JavaScript
36 lines
802 B
JavaScript
/** Used as references for various `Number` constants. */
|
|
var MAX_SAFE_INTEGER = 9007199254740991;
|
|
|
|
/**
|
|
* Checks if `value` is a valid array-like length.
|
|
*
|
|
* **Note:** This method is loosely based on
|
|
* [`ToLength`](http://ecma-international.org/ecma-262/7.0/#sec-tolength).
|
|
*
|
|
* @static
|
|
* @memberOf _
|
|
* @since 4.0.0
|
|
* @category Lang
|
|
* @param {*} value The value to check.
|
|
* @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
|
|
* @example
|
|
*
|
|
* _.isLength(3);
|
|
* // => true
|
|
*
|
|
* _.isLength(Number.MIN_VALUE);
|
|
* // => false
|
|
*
|
|
* _.isLength(Infinity);
|
|
* // => false
|
|
*
|
|
* _.isLength('3');
|
|
* // => false
|
|
*/
|
|
function isLength(value) {
|
|
return typeof value == 'number' &&
|
|
value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
|
|
}
|
|
|
|
module.exports = isLength;
|