So it is obvious that if you think it could be available in FileMaker.PerformScript. In this libarary, I made performScript function, which is a wrapper function of 'FileMaker.PerformScript' and ...

fmPromise.performScript (scriptName, parameter) Performs a FileMaker script, returning a Promise. The Promise will be resolved with the script result (parsed as JSON if possible), or rejected if the ...