merge.smart(
  {
    loaders: [
      {
        test: /\.js$/,
        loaders: ["babel"],
      },
    ],
  },
  {
    loaders: [
      {
        test: /\.js$/,
        loaders: ["react-hot", "babel"],
      },
    ],
  }
);
// will become
{
  loaders: [
    {
      test: /\.js$/,
      // order of second argument is respected
      loaders: ["react-hot", "babel"],
    },
  ];
}

const output = merge.smartStrategy(
  {
    entry: 'prepend', // or 'replace'
    'module.loaders': 'prepend'
  },
  ['LoaderOptionsPlugin']
)(object1, object2, object3, ...);

const a = {
  entry: ["foo"],
};
const b = {
  entry: [],
};

merge(a, b); // Yields a result, not b like before.

var output = merge({
  customizeArray(a, b, key) { return [...a, ...b]; },
  customizeObject(a, b, key) { return mergeWith(a, b); }
})(object1, object2, object3, ...);

var output = merge.strategy({
  entry: 'prepend',
  'module.loaders': 'prepend'
})(object1, object2, object3, ...);

var output = merge.smartStrategy({
  entry: 'prepend',
  'module.loaders': 'prepend'
})(object1, object2, object3, ...);