This is exactly what I have been looking for...

[mercmobily]

Hi,

This is precisely what I've been looking for.
Impressive!
Are you actively maintaining it? Are you using it in a production environment?

Finally... how would you go, if you were to support transpiling of Javascriptwithin HTML? (in a <script> element, that is)

Thank you!

Merc.

[matAtWork]

It is in production, and it does work, although it's not had much love recently - the kangax tables are probably out of date since there have been a few major releases of Chrome, FF and Safari at least.

It doesn't currently attempt to parse or understand scripts within HTML. This is a medium sized update, and with no demand at our end it's unlikely to get done, but feel free to update and submit a PR

[matAtWork]

...oh, and the list of ES features is incomplete (as per the README), since so far we've only implemented ones we use in our projects.

[mercmobily]

I am very, very interested in having real-time transpiling of code. I would like to push ahead features I need (especially when using Polymer), kangax tables and ES features. You open to 1) Accept help 2) Offer a bit of guidance at the beginning?

[matAtWork]

Definitely (2), and (1) if I get the time.

The main task is mapping the kangax identifiers (like arrow_functions) to the Babel plugins that support the feature (like babel-plugin-transform-es2015-arrow-functions). These are mapped in the block at https://github.com/MailOnline/transpile-middleware/blob/master/transpile.js#L36.

There are npm jobs (as specified in the README) to update the UA's and Kangax data - these should just run, although you should probably add some tests (there's a few very simple ones at present).

[mercmobily]

I just talked to the Babel developer. He suggested we use https://github.com/babel/babel-preset-env which is maintained and was created for the exact purpose of figuring out browser capability.

I am poking blind here, but is this something you would like to look into?

[matAtWork]

I'm not familiar with babel-preset-env, but it looks like it's doing something very similar. We're unlikely to change ourselves, since transpile-middleware does what we want, but I'd guess you'd get better support from the babel project, although that doesn't always apply to plugins.