time-to-botec

Benchmark sampling in different programming languages
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isEmpty.js (2000B)

      1 var baseKeys = require('./_baseKeys'),
      2     getTag = require('./_getTag'),
      3     isArguments = require('./isArguments'),
      4     isArray = require('./isArray'),
      5     isArrayLike = require('./isArrayLike'),
      6     isBuffer = require('./isBuffer'),
      7     isPrototype = require('./_isPrototype'),
      8     isTypedArray = require('./isTypedArray');
      9 
     10 /** `Object#toString` result references. */
     11 var mapTag = '[object Map]',
     12     setTag = '[object Set]';
     13 
     14 /** Used for built-in method references. */
     15 var objectProto = Object.prototype;
     16 
     17 /** Used to check objects for own properties. */
     18 var hasOwnProperty = objectProto.hasOwnProperty;
     19 
     20 /**
     21  * Checks if `value` is an empty object, collection, map, or set.
     22  *
     23  * Objects are considered empty if they have no own enumerable string keyed
     24  * properties.
     25  *
     26  * Array-like values such as `arguments` objects, arrays, buffers, strings, or
     27  * jQuery-like collections are considered empty if they have a `length` of `0`.
     28  * Similarly, maps and sets are considered empty if they have a `size` of `0`.
     29  *
     30  * @static
     31  * @memberOf _
     32  * @since 0.1.0
     33  * @category Lang
     34  * @param {*} value The value to check.
     35  * @returns {boolean} Returns `true` if `value` is empty, else `false`.
     36  * @example
     37  *
     38  * _.isEmpty(null);
     39  * // => true
     40  *
     41  * _.isEmpty(true);
     42  * // => true
     43  *
     44  * _.isEmpty(1);
     45  * // => true
     46  *
     47  * _.isEmpty([1, 2, 3]);
     48  * // => false
     49  *
     50  * _.isEmpty({ 'a': 1 });
     51  * // => false
     52  */
     53 function isEmpty(value) {
     54   if (value == null) {
     55     return true;
     56   }
     57   if (isArrayLike(value) &&
     58       (isArray(value) || typeof value == 'string' || typeof value.splice == 'function' ||
     59         isBuffer(value) || isTypedArray(value) || isArguments(value))) {
     60     return !value.length;
     61   }
     62   var tag = getTag(value);
     63   if (tag == mapTag || tag == setTag) {
     64     return !value.size;
     65   }
     66   if (isPrototype(value)) {
     67     return !baseKeys(value).length;
     68   }
     69   for (var key in value) {
     70     if (hasOwnProperty.call(value, key)) {
     71       return false;
     72     }
     73   }
     74   return true;
     75 }
     76 
     77 module.exports = isEmpty;