Bad Compile Target

/**
 * let/count=0
 * const/doubleCount=count*2
 * if=Math.random() > 0.5
 *  button onClick(){count++}
 *    -- Value: ${count}, Double: ${doubleCount}
 * effect() {
 *   console.log(count);
 * }
 */

const $ = section("index.marko");
const $if_then = section("index.marko$if_then");

const $count = signal($, "count", () => [$doubleCount, $onClick, $effect]);
const $setup_count = setupSignal($count, () => 0);
const $doubleCount = compute($, "doubleCount", ({ count }) => count * 2);
const $if_test = () => Math.random() > 0.5; // can also be a compute.
const $onClick = on($if_then, "btn", "click", ({ count }, s) => () => {
  $count(s, count + 1);
});
const $effect = effect($, ({ count }) => {
  console.log(count);
});

const $fooAttr = attr($if_then, "btn:foo:count");
const $barAttr = attr($if_then, "btn", "bar", () => $count);

const $if = condition(
  $if_test,
  template(
    $if_then,
    $onClick,
    el("button", {
        id: "btn",
        attrs: [
            "class=hello",
            $fooAttr,
            attr("bar", $count)
        ],
        children: [
            "Value: ",
            text($count),
            "Double: ",
            text($doubleCount),
        ]
    })
  ),
);
// default export
const t = template($, $setup_count, $if);

// STUB RUNTIME.

/*@__NO_SIDE_EFFECTS__*/
function section(id) {
  return { id };
}

/*@__NO_SIDE_EFFECTS__*/
function template(section, ...parts) {
  return {
    section,
    parts,
  };
}

/*@__NO_SIDE_EFFECTS__*/
function condition(signal, consequent, alternate) {
  return {
    signal,
    consequent,
    alternate,
  };
}

/*@__NO_SIDE_EFFECTS__*/
function text(section, name) {
  return { section, name };
}

/*@__NO_SIDE_EFFECTS__*/
function el(name) {
  return { name };
}

/*@__NO_SIDE_EFFECTS__*/
function signal(section, name, subscribers) {
  return {
    section,
    name,
    subscribers,
  };
}

/*@__NO_SIDE_EFFECTS__*/
function setupSignal(signal, initialValue) {
  return {
    signal,
    initialValue,
  };
}

/*@__NO_SIDE_EFFECTS__*/
function compute(section, name, fn, subscribers) {
  return {
    section,
    name,
    fn,
    subscribers,
  };
}

function on(section, el, event, signals, fn) {
  console.log("NOT PURE");
  return {
    section,
    el,
    event,
    signals,
    fn,
  };
}

function effect(signals, fn) {
  console.log("NOT PURE");
  return {
    signals,
    fn,
  };
}