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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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