Asynchronous exception handling with bluebird promises

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Promises are not domains, they will not catch exceptions from asynchronous callbacks. You just can’t do that.

Promises do however catch exceptions that are thrown from within a then / catch / Promise constructor callback. So use

function getPromise(){
    return new Promise(function(done, reject){
        setTimeout(done, 500);
    }).then(function() {
        console.log("hihihihi");
        throw new Error("Oh no!");
    });
}

(or just Promise.delay) to get the desired behaviour. Never throw in custom (non-promise) async callbacks, always reject the surrounding promise. Use try-catch if it really needs to be.

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