Question: Reverse mode

[enzonotario]

Hi there!

Is there any way to run transformations in "reverse mode"? so that I can get the original code back from the transformed code.

Thanks!

[coderaiser]

There is no such a feature, anyways there is a couple ways you can achieve this:

• use git commit to save your code before running 🐊Putout to see if applied changes is good for you, or you need to got checkout —- . and disable some rules.
• You can use eslint-plugin-putout with ESLint or inside IDE of your choice, so all dangerous rules will be disabled.
• You can use redlint pack to save state of your repo and redlint extract to restore the state, before each run of putout —-fix.
• We can use (or develop, but I thin git and redlint is good enough for this purpose 🤔) some tool to save the state of your codebase.
• We can add a new flag —-backup to store backup in a temporary file in node_modules in the similar way enabled by default cache works.

What option do you think would be the best?

[enzonotario]

Well, maybe I'm wrong but let me explain what I want to do:

I have a little project EsJS that wants to "extend" JavaScript with Spanish keywords. Of course, I saw your Goldstein project, but I want to try Putout without extending Acorn.

For now, my little project does a basic transpilation, by tokenizing the code and just looking for a translation. I want to improve a bit more this, and was trying to use Putout. It works fine for EsJS -> JS, but I also want to have a bi-directional transpilation.

As Putout works for me in a way, I wonder if I can transform the code in the other way to replace my "basic transpilation" with Putout (and then look up for more improvements).

So, the options you mentioned don't resolve my needs... I think I could write my "reverse rules" to do this. But, also maybe I'm doing this wrong, and will have to do this in others ways. What do you think? Thanks in advance!

[coderaiser]

Yes, 🤫Goldstein can help you do to what you want with help of:

• print;
• convert;

But the most important thing is @putout/printer, you can override it in any way you want using Babel AST, here is example.

[enzonotario]

Nice, thank you so much!

I've checked Goldstein but I was looking at the Acorn Extension (here for example). I'll check the Printer more in depth! Thanks!