Forms have all these advanced features like logic in various formats (javascript, json, etc) and I don’t find documentation for it anywhere.
This is true and we will look into improving the Forms documentation. It has many cool hidden features.
In the meantime, we welcome any contributions to our Tutorials category that could help our users out 
ashokkarale
Anil_G
Yoichi
yangyq10
postwick
chandreshsinh.jadeja
aravindbalineni123
Parvathy
aya
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