/** * lodash (Custom Build) * Build: `lodash modularize exports="npm" -o ./` * Copyright jQuery Foundation and other contributors * Released under MIT license * Based on Underscore.js 1.8.3 * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors */ /** Used as references for various `Number` constants. */ var MAX_SAFE_INTEGER = 9007199254740991; /** `Object#toString` result references. */ var argsTag = '[object Arguments]', funcTag = '[object Function]', genTag = '[object GeneratorFunction]', mapTag = '[object Map]', objectTag = '[object Object]', promiseTag = '[object Promise]', setTag = '[object Set]', weakMapTag = '[object WeakMap]'; var dataViewTag = '[object DataView]'; /** * Used to match `RegExp` * [syntax characters](http://ecma-international.org/ecma-262/7.0/#sec-patterns). */ var reRegExpChar = /[\\^$.*+?()[\]{}|]/g; /** Used to detect host constructors (Safari). */ var reIsHostCtor = /^\[object .+?Constructor\]$/; /** Detect free variable `global` from Node.js. */ var freeGlobal = typeof global == 'object' && global && global.Object === Object && global; /** Detect free variable `self`. */ var freeSelf = typeof self == 'object' && self && self.Object === Object && self; /** Used as a reference to the global object. */ var root = freeGlobal || freeSelf || Function('return this')(); /** Detect free variable `exports`. */ var freeExports = typeof exports == 'object' && exports && !exports.nodeType && exports; /** Detect free variable `module`. */ var freeModule = freeExports && typeof module == 'object' && module && !module.nodeType && module; /** Detect the popular CommonJS extension `module.exports`. */ var moduleExports = freeModule && freeModule.exports === freeExports; /** * Gets the value at `key` of `object`. * * @private * @param {Object} [object] The object to query. * @param {string} key The key of the property to get. * @returns {*} Returns the property value. */ function getValue(object, key) { return object == null ? undefined : object[key]; } /** * Checks if `value` is a host object in IE < 9. * * @private * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is a host object, else `false`. */ function isHostObject(value) { // Many host objects are `Object` objects that can coerce to strings // despite having improperly defined `toString` methods. var result = false; if (value != null && typeof value.toString != 'function') { try { result = !!(value + ''); } catch (e) {} } return result; } /** * Creates a unary function that invokes `func` with its argument transformed. * * @private * @param {Function} func The function to wrap. * @param {Function} transform The argument transform. * @returns {Function} Returns the new function. */ function overArg(func, transform) { return function(arg) { return func(transform(arg)); }; } /** Used for built-in method references. */ var funcProto = Function.prototype, objectProto = Object.prototype; /** Used to detect overreaching core-js shims. */ var coreJsData = root['__core-js_shared__']; /** Used to detect methods masquerading as native. */ var maskSrcKey = (function() { var uid = /[^.]+$/.exec(coreJsData && coreJsData.keys && coreJsData.keys.IE_PROTO || ''); return uid ? ('Symbol(src)_1.' + uid) : ''; }()); /** Used to resolve the decompiled source of functions. */ var funcToString = funcProto.toString; /** Used to check objects for own properties. */ var hasOwnProperty = objectProto.hasOwnProperty; /** * Used to resolve the * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring) * of values. */ var objectToString = objectProto.toString; /** Used to detect if a method is native. */ var reIsNative = RegExp('^' + funcToString.call(hasOwnProperty).replace(reRegExpChar, '\\$&') .replace(/hasOwnProperty|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$' ); /** Built-in value references. */ var Buffer = moduleExports ? root.Buffer : undefined, propertyIsEnumerable = objectProto.propertyIsEnumerable; /* Built-in method references for those with the same name as other `lodash` methods. */ var nativeIsBuffer = Buffer ? Buffer.isBuffer : undefined, nativeKeys = overArg(Object.keys, Object); /* Built-in method references that are verified to be native. */ var DataView = getNative(root, 'DataView'), Map = getNative(root, 'Map'), Promise = getNative(root, 'Promise'), Set = getNative(root, 'Set'), WeakMap = getNative(root, 'WeakMap'); /** Detect if properties shadowing those on `Object.prototype` are non-enumerable. */ var nonEnumShadows = !propertyIsEnumerable.call({ 'valueOf': 1 }, 'valueOf'); /** Used to detect maps, sets, and weakmaps. */ var dataViewCtorString = toSource(DataView), mapCtorString = toSource(Map), promiseCtorString = toSource(Promise), setCtorString = toSource(Set), weakMapCtorString = toSource(WeakMap); /** * The base implementation of `getTag`. * * @private * @param {*} value The value to query. * @returns {string} Returns the `toStringTag`. */ function baseGetTag(value) { return objectToString.call(value); } /** * The base implementation of `_.isNative` without bad shim checks. * * @private * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is a native function, * else `false`. */ function baseIsNative(value) { if (!isObject(value) || isMasked(value)) { return false; } var pattern = (isFunction(value) || isHostObject(value)) ? reIsNative : reIsHostCtor; return pattern.test(toSource(value)); } /** * Gets the native function at `key` of `object`. * * @private * @param {Object} object The object to query. * @param {string} key The key of the method to get. * @returns {*} Returns the function if it's native, else `undefined`. */ function getNative(object, key) { var value = getValue(object, key); return baseIsNative(value) ? value : undefined; } /** * Gets the `toStringTag` of `value`. * * @private * @param {*} value The value to query. * @returns {string} Returns the `toStringTag`. */ var getTag = baseGetTag; // Fallback for data views, maps, sets, and weak maps in IE 11, // for data views in Edge < 14, and promises in Node.js. if ((DataView && getTag(new DataView(new ArrayBuffer(1))) != dataViewTag) || (Map && getTag(new Map) != mapTag) || (Promise && getTag(Promise.resolve()) != promiseTag) || (Set && getTag(new Set) != setTag) || (WeakMap && getTag(new WeakMap) != weakMapTag)) { getTag = function(value) { var result = objectToString.call(value), Ctor = result == objectTag ? value.constructor : undefined, ctorString = Ctor ? toSource(Ctor) : undefined; if (ctorString) { switch (ctorString) { case dataViewCtorString: return dataViewTag; case mapCtorString: return mapTag; case promiseCtorString: return promiseTag; case setCtorString: return setTag; case weakMapCtorString: return weakMapTag; } } return result; }; } /** * Checks if `func` has its source masked. * * @private * @param {Function} func The function to check. * @returns {boolean} Returns `true` if `func` is masked, else `false`. */ function isMasked(func) { return !!maskSrcKey && (maskSrcKey in func); } /** * Checks if `value` is likely a prototype object. * * @private * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is a prototype, else `false`. */ function isPrototype(value) { var Ctor = value && value.constructor, proto = (typeof Ctor == 'function' && Ctor.prototype) || objectProto; return value === proto; } /** * Converts `func` to its source code. * * @private * @param {Function} func The function to process. * @returns {string} Returns the source code. */ function toSource(func) { if (func != null) { try { return funcToString.call(func); } catch (e) {} try { return (func + ''); } catch (e) {} } return ''; } /** * Checks if `value` is likely an `arguments` object. * * @static * @memberOf _ * @since 0.1.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is an `arguments` object, * else `false`. * @example * * _.isArguments(function() { return arguments; }()); * // => true * * _.isArguments([1, 2, 3]); * // => false */ function isArguments(value) { // Safari 8.1 makes `arguments.callee` enumerable in strict mode. return isArrayLikeObject(value) && hasOwnProperty.call(value, 'callee') && (!propertyIsEnumerable.call(value, 'callee') || objectToString.call(value) == argsTag); } /** * Checks if `value` is classified as an `Array` object. * * @static * @memberOf _ * @since 0.1.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is an array, else `false`. * @example * * _.isArray([1, 2, 3]); * // => true * * _.isArray(document.body.children); * // => false * * _.isArray('abc'); * // => false * * _.isArray(_.noop); * // => false */ var isArray = Array.isArray; /** * Checks if `value` is array-like. A value is considered array-like if it's * not a function and has a `value.length` that's an integer greater than or * equal to `0` and less than or equal to `Number.MAX_SAFE_INTEGER`. * * @static * @memberOf _ * @since 4.0.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is array-like, else `false`. * @example * * _.isArrayLike([1, 2, 3]); * // => true * * _.isArrayLike(document.body.children); * // => true * * _.isArrayLike('abc'); * // => true * * _.isArrayLike(_.noop); * // => false */ function isArrayLike(value) { return value != null && isLength(value.length) && !isFunction(value); } /** * This method is like `_.isArrayLike` except that it also checks if `value` * is an object. * * @static * @memberOf _ * @since 4.0.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is an array-like object, * else `false`. * @example * * _.isArrayLikeObject([1, 2, 3]); * // => true * * _.isArrayLikeObject(document.body.children); * // => true * * _.isArrayLikeObject('abc'); * // => false * * _.isArrayLikeObject(_.noop); * // => false */ function isArrayLikeObject(value) { return isObjectLike(value) && isArrayLike(value); } /** * Checks if `value` is a buffer. * * @static * @memberOf _ * @since 4.3.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is a buffer, else `false`. * @example * * _.isBuffer(new Buffer(2)); * // => true * * _.isBuffer(new Uint8Array(2)); * // => false */ var isBuffer = nativeIsBuffer || stubFalse; /** * 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 (isArrayLike(value) && (isArray(value) || typeof value == 'string' || typeof value.splice == 'function' || isBuffer(value) || isArguments(value))) { return !value.length; } var tag = getTag(value); if (tag == mapTag || tag == setTag) { return !value.size; } if (nonEnumShadows || isPrototype(value)) { return !nativeKeys(value).length; } for (var key in value) { if (hasOwnProperty.call(value, key)) { return false; } } return true; } /** * Checks if `value` is classified as a `Function` object. * * @static * @memberOf _ * @since 0.1.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is a function, else `false`. * @example * * _.isFunction(_); * // => true * * _.isFunction(/abc/); * // => false */ function isFunction(value) { // The use of `Object#toString` avoids issues with the `typeof` operator // in Safari 8-9 which returns 'object' for typed array and other constructors. var tag = isObject(value) ? objectToString.call(value) : ''; return tag == funcTag || tag == genTag; } /** * 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; } /** * Checks if `value` is the * [language type](http://www.ecma-international.org/ecma-262/7.0/#sec-ecmascript-language-types) * of `Object`. (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`) * * @static * @memberOf _ * @since 0.1.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is an object, else `false`. * @example * * _.isObject({}); * // => true * * _.isObject([1, 2, 3]); * // => true * * _.isObject(_.noop); * // => true * * _.isObject(null); * // => false */ function isObject(value) { var type = typeof value; return !!value && (type == 'object' || type == 'function'); } /** * Checks if `value` is object-like. A value is object-like if it's not `null` * and has a `typeof` result of "object". * * @static * @memberOf _ * @since 4.0.0 * @category Lang * @param {*} value The value to check. * @returns {boolean} Returns `true` if `value` is object-like, else `false`. * @example * * _.isObjectLike({}); * // => true * * _.isObjectLike([1, 2, 3]); * // => true * * _.isObjectLike(_.noop); * // => false * * _.isObjectLike(null); * // => false */ function isObjectLike(value) { return !!value && typeof value == 'object'; } /** * This method returns `false`. * * @static * @memberOf _ * @since 4.13.0 * @category Util * @returns {boolean} Returns `false`. * @example * * _.times(2, _.stubFalse); * // => [false, false] */ function stubFalse() { return false; } module.exports = isEmpty;