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/**
* lodash (Custom Build) <https://lodash.com/>
* Build: `lodash modularize exports="npm" -o ./`
* Copyright jQuery Foundation and other contributors <https://jquery.org/>
* Released under MIT license <https://lodash.com/license>
* Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
* Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
*/
/** `Object#toString` result references. */
var objectTag = '[object Object]';
/**
* 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 resolve the decompiled source of functions. */
var funcToString = funcProto.toString;
/** Used to check objects for own properties. */
var hasOwnProperty = objectProto.hasOwnProperty;
/** Used to infer the `Object` constructor. */
var objectCtorString = funcToString.call(Object);
/**
* Used to resolve the
* [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
* of values.
*/
var objectToString = objectProto.toString;
/** Built-in value references. */
var getPrototype = overArg(Object.getPrototypeOf, Object);
/**
* 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';
}
/**
* Checks if `value` is a plain object, that is, an object created by the
* `Object` constructor or one with a `[[Prototype]]` of `null`.
*
* @static
* @memberOf _
* @since 0.8.0
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a plain object, else `false`.
* @example
*
* function Foo() {
* this.a = 1;
* }
*
* _.isPlainObject(new Foo);
* // => false
*
* _.isPlainObject([1, 2, 3]);
* // => false
*
* _.isPlainObject({ 'x': 0, 'y': 0 });
* // => true
*
* _.isPlainObject(Object.create(null));
* // => true
*/
function isPlainObject(value) {
if (!isObjectLike(value) ||
objectToString.call(value) != objectTag || isHostObject(value)) {
return false;
}
var proto = getPrototype(value);
if (proto === null) {
return true;
}
var Ctor = hasOwnProperty.call(proto, 'constructor') && proto.constructor;
return (typeof Ctor == 'function' &&
Ctor instanceof Ctor && funcToString.call(Ctor) == objectCtorString);
}
module.exports = isPlainObject;
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