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

gulp.task('build', () =>
    gulp.src('src/**/*.js')
        .pipe(babel())
        .pipe(gulp.dest('dist'))
);

@@ -174,8 +174,121 @@
 t'))%0A);%0A
+%0Agulp.task('watch', () =%3E%0A    gulp.watch('src/**/*.js', %5B'build'%5D)%0A);%0A%0Agulp.task('default', %5B'build', 'watch'%5D);%0A

add watch