Is it possible to set choices in a dropdown by some function?

Is it possible to set choices in a dropdown by some function?

Something like this

Code
{
                "type": "dropdown",
                "name": "Catg3",
                "title": "Catg3",
                "choices": "getCatgOptions()"
            },

where getCatgOption return an array of string

Code
function getCatgOptions() {
     let catgArray: string[] = [];
     categoryDataJson.forEach((catg: CategoryData) => {
         catgArray.push(catg.Category);
     });
     return catgArray;
 }

 Survey.FunctionFactory.Instance.register('getCatgOptions', getCatgOptions);