I use Gulp as task manager and Babel for convert my ES6 program to a version that is understandable for browsers, not for Node!

```
const gulp = require('gulp');
const babel = require('gulp-babel');

gulp.task('default', () =>
    gulp.src('src/app.js')
        .pipe(babel({
            presets: ['es2015']
        }))
        .pipe(gulp.dest('dist'))
);

```

and in `src/app.js` I have:

```
import { square, diag } from 'lib';
//Some code here....

```

But, when I run the gulp, it make a file in `dist` but it converts `import` which is in `app.js` file to `require` keyword that is not understandable for browsers... I thought bable will merge `imported` files in `src/app.js` to one file in `dist`

How can I convert my library code to be supported by browsers using Babel?