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Comment by kozhevnikov | Hacker News Reader

One of the unexpected behaviours was that if you proxy an object you cannot call it as a function even if you define `apply` handler. This made proxying async functions impossible because they always return Promise<T> even if T is another function, unless you wrap promise in a dummy function before proxying.

https://github.com/kozhevnikov/proxymise/blob/master/index.j...

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That is really interesting, I'm building something with Proxies for any Type and async function proxified worked for me. Mind if I hit you up for a chat?

Sure. I mean if you have an async function that returns another function (so it actually returns a promise of a function because it's async) proxy of the original function will call apply handler when invoked, but proxy of the return value will not because it's actually not a function but an object (a promise of a function) and as it turned out proxied objects do not call apply handler when invoked (even if it's defined) but throw an exception.

    const handler = { apply: () => { console.log('ok') } };
    const foo = new Proxy(() => {}, handler);
    const bar = new Proxy({}, handler);

    > foo()
    < ok
    > bar()
    < VM313:1 Uncaught TypeError: bar is not a function
        at <anonymous>:1:1

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