Function merge

MathBox/mathbox-bundle.js:37812–37840

* Recursively merges own enumerable properties of the source object(s), that * don't resolve to `undefined` into the destination object. Subsequent sources * will overwrite property assignments of previous sources. If a callback is * provided it will be executed to produce the merged

(object)

     * // => { 'fruits': ['apple', 'banana'], 'vegetables': ['beet', 'carrot] }
     */
    function merge(object) {
      var args = arguments,
          length = 2;

      if (!isObject(object)) {
        return object;
      }
      // allows working with `_.reduce` and `_.reduceRight` without using
      // their `index` and `collection` arguments
      if (typeof args[2] != 'number') {
        length = args.length;
      }
      if (length > 3 && typeof args[length - 2] == 'function') {
        var callback = baseCreateCallback(args[--length - 1], args[length--], 2);
      } else if (length > 2 && typeof args[length - 1] == 'function') {
        callback = args[--length];
      }
      var sources = slice(arguments, 1, length),
          index = -1,
          stackA = getArray(),
          stackB = getArray();

      while (++index < length) {
        baseMerge(object, sources[index], callback, stackA, stackB);
      }
      releaseArray(stackA);
      releaseArray(stackB);
      return object;
    }

    /**
     * Creates a shallow clone of `object` excluding the specified properties.