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- var baseKeys = require('./_baseKeys'),
- getTag = require('./_getTag'),
- isArguments = require('./isArguments'),
- isArray = require('./isArray'),
- isArrayLike = require('./isArrayLike'),
- isBuffer = require('./isBuffer'),
- isPrototype = require('./_isPrototype'),
- isTypedArray = require('./isTypedArray');
- /** `Object#toString` result references. */
- var mapTag = '[object Map]',
- setTag = '[object Set]';
- /** Used for built-in method references. */
- var objectProto = Object.prototype;
- /** Used to check objects for own properties. */
- var hasOwnProperty = objectProto.hasOwnProperty;
- /**
- * Checks if `value` is an empty object, collection, map, or set.
- *
- * Objects are considered empty if they have no own enumerable string keyed
- * properties.
- *
- * Array-like values such as `arguments` objects, arrays, buffers, strings, or
- * jQuery-like collections are considered empty if they have a `length` of `0`.
- * Similarly, maps and sets are considered empty if they have a `size` of `0`.
- *
- * @static
- * @memberOf _
- * @since 0.1.0
- * @category Lang
- * @param {*} value The value to check.
- * @returns {boolean} Returns `true` if `value` is empty, else `false`.
- * @example
- *
- * _.isEmpty(null);
- * // => true
- *
- * _.isEmpty(true);
- * // => true
- *
- * _.isEmpty(1);
- * // => true
- *
- * _.isEmpty([1, 2, 3]);
- * // => false
- *
- * _.isEmpty({ 'a': 1 });
- * // => false
- */
- function isEmpty(value) {
- if (value == null) {
- return true;
- }
- if (isArrayLike(value) &&
- (isArray(value) || typeof value == 'string' || typeof value.splice == 'function' ||
- isBuffer(value) || isTypedArray(value) || isArguments(value))) {
- return !value.length;
- }
- var tag = getTag(value);
- if (tag == mapTag || tag == setTag) {
- return !value.size;
- }
- if (isPrototype(value)) {
- return !baseKeys(value).length;
- }
- for (var key in value) {
- if (hasOwnProperty.call(value, key)) {
- return false;
- }
- }
- return true;
- }
- module.exports = isEmpty;
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