const { Preprocessor } = require('content-tag');

const p = new Preprocessor();

const res = p.process(`
f = function(this: Context, ...args) {
    function t(this: Context, ...args) {};
    <template></template>
}`);

console.log(res);

import { template } from "@ember/template-compiler";
f = function(this: Context, ...args) {
   function t(this1: Context, ...args1) {}
   ;
   template(``, {
       eval () {
           return eval(arguments[0]);
       }
   });
};