docs: function baseClone(value, isDeep, isFull, customizer, key, object, stack) {
      var result;
      if (customizer) {
        result = object ? customizer(value, key, object, stack) : customizer(value);
      }
      if (result !== undefined) {
        return result;
      }
      if (!isObject(value)) {
        return value;
      }
      var isArr = isArray(value);
      if (isArr) {
        result = initCloneArray(value);
        if (!isDeep) {
          return copyArray(value, result);
        }
      } else {
        var tag = getTag(value),
            isFunc = tag == funcTag || tag == genTag;
  
        if (isBuffer(value)) {
          return cloneBuffer(value, isDeep);
        }
        if (tag == objectTag || tag == argsTag || isFunc && !object) {
          if (isHostObject(value)) {
            return object ? value : {};
          }
          result = initCloneObject(isFunc ? {} : value);
          if (!isDeep) {
            return copySymbols(value, baseAssign(result, value));
          }
        } else {
          if (!cloneableTags[tag]) {
            return object ? value : {};
          }
          result = initCloneByTag(value, tag, baseClone, isDeep);
        }
      }
      // Check for circular references and return its corresponding clone.
      stack || (stack = new Stack());
      var stacked = stack.get(value);
      if (stacked) {
        return stacked;
      }
      stack.set(value, result);
  
      if (!isArr) {
        var props = isFull ? getAllKeys(value) : keys(value);
      }
      arrayEach(props || value, function (subValue, key) {
        if (props) {
          key = subValue;
          subValue = value[key];
        }
        // Recursively populate clone (susceptible to call stack limits).
        assignValue(result, key, baseClone(subValue, isDeep, isFull, customizer, key, value, stack));
      });
      return result;
    }