How to derive a field, applying toLocaleString function?

[aborruso]

Hi,
I know I cannot write the below code because "Table expressions do not support closures. Use aq.escape(fn) to use a function as-is (including closures), or use aq.addFunction(name, fn) to add new op functions."

myData.derive({ v: (d) => d["value"].toLocaleString("it-IT")})

I'm sure there is a way to do it. Is there any hello world example?

Thank you