Trying to use handlebars-helpers in browser, cannot bablify completely with browserify

[happyvig]

Hi,
I need to use handlebars-helpers in my browser web app.

I referred this as per documentation :
https://github.com/doowb/handlebars-helpers-browserify-example

But this didnt had any mention about babelify. Looks like some dependent node_module called 'striptags' used ES6 const notation. I tried adding bablify into the browserify workflow. But the resultant app.js inside gh_pages folder still had const notation and not completely transpiled.

app.js : require('handlebars-helpers')({ handlebars: Handlebars });

_gh_pages/app.js : (notice this file still has const ES6 notation and not 'var' notation)

 .....
  const STATE_PLAINTEXT = Symbol('plaintext');
  const STATE_HTML      = Symbol('html');
  const STATE_COMMENT   = Symbol('comment');

  const ALLOWED_TAGS_REGEX  = /<(\w*)>/g;
  const NORMALIZE_TAG_REGEX = /<\/?([^\s\/>]+)/;

  function striptags(html, allowable_tags, tag_replacement) { ... }
   .....

gulpfile.js

.....
var babelify = require('babelify');
gulp.task('**browserify**', function () {
  var b = browserify({
    entries: './src/app.js',
    debug: false,
    external: 'Handlebars'
  })**.transform(babelify, { presets: ["es2015"],  extensions: ['.js', '.ts'] })**;

  // ignore the internal handlebars require
  b.ignore('handlebars');

  return b.bundle()
    .pipe(source('app.js'))
    .pipe(buffer())
    //.pipe(uglify())
    .pipe(gulp.dest('./_gh_pages/'))
    .pipe(browserSync.stream());
});
......