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