import getTag from './getTag.js' import isArguments from './isArguments.js' import isArrayLike from './isArrayLike.js' import isBuffer from './isBuffer.js' import isPrototype from './isPrototype.js' import isTypedArray from './isTypedArray.js' /** Used to check objects for own properties. */ const hasOwnProperty = Object.prototype.hasOwnProperty /** * Checks if `value` is an empty object, collection, map, or set. * 检查' value '是否为空对象、集合、映射或集合。 * Objects are considered empty if they have no own enumerable string keyed * properties. * 如果对象没有自己的可枚举字符串作为键,则认为它们是空的 * 属性。 * 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`. * 类似数组的值,如‘arguments’对象、数组、缓冲区、字符串或 * 类似于jquery的集合如果“长度”为“0”,就会被认为是空的。 * 类似地,如果映射和集合的“size”为“0”,则认为它们是空的。 * @since 0.1.0 * @category Lang * @param {*} value 要检查的值。 * @returns {boolean} 如果' value '为空,则返回' true ',否则返回' false '。 * @example * * isEmpty(null) * // => true * * isEmpty(true) * // => true * * isEmpty(1) * // => true * * isEmpty([1, 2, 3]) * // => false * * isEmpty('abc') * // => false * * isEmpty({ 'a': 1 }) * // => false */ function isEmpty(value) { if (value == null) { return true } if (isArrayLike(value) && (Array.isArray(value) || typeof value === 'string' || typeof value.splice === 'function' || isBuffer(value) || isTypedArray(value) || isArguments(value))) { return !value.length } const tag = getTag(value) if (tag == '[object Map]' || tag == '[object Set]') { return !value.size } if (isPrototype(value)) { return !Object.keys(value).length } for (const key in value) { if (hasOwnProperty.call(value, key)) { return false } } return true } export default isEmpty