`Cont` monad being used for code generation (used as a Reified Monad)

index.ts

import { Cont, do_, exec, execR, } from "prelude";

let freeVar = 0;
let code = "";

function main(): Cont<void> {
    return do_(() => {
        let name = ask(_("What is your name?"));
        print(append(_("Hello "), name));
    });
}

console.log(compile(main()));

function allocVar(): string {
    return `x${freeVar++}`;
}

function compile(x: Cont<void>) {
    let outer = code;
    try {
        code = "";
        x.run();
        code = code
            .split("\r\n")
            .filter((line) => line != "")
            .map((line) => `  ${line}`)
            .join("\r\n");
        return `function() {\r\n${code}\r\n}`;
    } finally {
        code = outer;
    }
}

function ask(msg: Cont<string>): Cont<string> {
    return execR(msg.then((msg) => Cont.of((k) => {
        let v = allocVar();
        code += `let ${v} = window.prompt(${msg})\r\n`;
        k(v);
    })));
}

function print(v: Cont<string>) {
    exec(v.then((v) => Cont.of((k) => {
        code += `console.log(${v}};\r\n`;
        k();
    })));
}

function append(a: Cont<string>, b: Cont<string>): Cont<string> {
    return execR(a.then((a) => b.then((b) => Cont.of((k) => {
        let v = allocVar();
        code += `let ${v} = ${a} + ${b};\r\n`;
        k(v);
    }))));
}

function _(x: string): Cont<string> {
    return execR(Cont.of((k) => {
        let v = allocVar();
        code += `let ${v} = "${x}";\r\n`;
        k(v);
    }));
}

export function onUnload() {    
}