Is it possible to only convert a dart function to javascript

I am currently using the following package where the readme illustrates the following

final bool loaded = await JsIsolatedWorker().importScripts(['test.js']);

I am using the isolate worker package so my code can work on web and outside of web. I would like to generate javascript code from my dart code. I have one file with a top level function and I use

dart compile js -O0 -o test.js test.dart

which I found here

https://dart.dev/tools/dart2js

this is my dart file

void main(List<String> args) {
  doComputation('');
}
            
String doComputation(String input) {
  return 'output';
}

I can generate javascript only if I have a main function but this generates a javascript file where the doComutation is not a top level function, so I am not sure if the package can call the function. It looks like it generates an entire program instead of just generating one function.

The generated file is too long to post

So what my question comes down to is this. Is there a way to generate javascript from dart for 1 function with its dependencies included instead of having to generate the entire program? So that I can call this function from dart.

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