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- var baseRest = require('./_baseRest'),
- eq = require('./eq'),
- isIterateeCall = require('./_isIterateeCall'),
- keysIn = require('./keysIn');
-
- /** Used for built-in method references. */
- var objectProto = Object.prototype;
-
- /** Used to check objects for own properties. */
- var hasOwnProperty = objectProto.hasOwnProperty;
-
- /**
- * Assigns own and inherited enumerable string keyed properties of source
- * objects to the destination object for all destination properties that
- * resolve to `undefined`. Source objects are applied from left to right.
- * Once a property is set, additional values of the same property are ignored.
- *
- * **Note:** This method mutates `object`.
- *
- * @static
- * @since 0.1.0
- * @memberOf _
- * @category Object
- * @param {Object} object The destination object.
- * @param {...Object} [sources] The source objects.
- * @returns {Object} Returns `object`.
- * @see _.defaultsDeep
- * @example
- *
- * _.defaults({ 'a': 1 }, { 'b': 2 }, { 'a': 3 });
- * // => { 'a': 1, 'b': 2 }
- */
- var defaults = baseRest(function(object, sources) {
- object = Object(object);
-
- var index = -1;
- var length = sources.length;
- var guard = length > 2 ? sources[2] : undefined;
-
- if (guard && isIterateeCall(sources[0], sources[1], guard)) {
- length = 1;
- }
-
- while (++index < length) {
- var source = sources[index];
- var props = keysIn(source);
- var propsIndex = -1;
- var propsLength = props.length;
-
- while (++propsIndex < propsLength) {
- var key = props[propsIndex];
- var value = object[key];
-
- if (value === undefined ||
- (eq(value, objectProto[key]) && !hasOwnProperty.call(object, key))) {
- object[key] = source[key];
- }
- }
- }
-
- return object;
- });
-
- module.exports = defaults;
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