js_is_sane.js

const printOnce = function (data) {
  let printed = false;
  return function () {
    if (!printed) {
      console.log(data.byteLength);
    }
    printed = true;
  };
};
function demo() {
  const bigArrayBuffer = new ArrayBuffer(100_000_000);
  for (let i = 0; i < bigArrayBuffer.byteLength; i++) {
    bigArrayBuffer[i] = 0;
  }
  const trigger = printOnce(bigArrayBuffer);
  return trigger;
}

globalThis.triggerDemo = demo();
globalThis.triggerDemo();
globalThis.triggerDemo(); // noop, but memory is still reachable