Ashnazg Enterprises LLCQuantum Promise
It's like a promise, but with more lazy procrastination: it only starts once you await or .then() it.
js
const qp = require('quantum-promise'); // https://ashnazg.com/docs/lib/quantum-promise
async function dowork() {
console.log("running");
await q.delay(1000);
console.log("done");
}
const promise = qp(dowork);
console.log("about to run");
await promise;Is used as a mix-in
An object can become an awaitable deferred action by using this as a mix-in, and can replace the run() behavior after creation but before awaiting:
js
class Foo {
constructor() {
Object.assign(this, qp(this.doDefault));
}
doDefault() {
console.log("default action that's triggered by await");
}
configEdgeCase() {
this[qp.run] = () => {
console.log("running edge case");
};
}
}
const foo = new Foo();
foo.configEdgeCase();
await foo;All this weirdness allows squirrelnado to express ETL jobs with the following await => commence syntax, because I dislike verbose boilerplate:
const {read} = require('@ashnazg/squirrelnado');
const rows = await read('db://endpoint/tablefoo'); // the lack of any explicit termination means "resolve to array of rows"
// or instead of calling await on the opening step, chain them and await the last:
await read('db://endpoint/tablefoo').map(row => {
row.calc = 42;
return row;
}).write('db://endpoint/report_table');