fetch-ae.js

const fetch = new Effect();

function double() {
  const x = fetch.throw("number");
  return x * 2
}

try {
  double()
} fetch.catch(resume, ...args) {
  // resume lets double() continue running with the value!
  if (property === "number") {
    API.get("/number").then(
      response => resume(response.data.number)
    )
  }
}