Shouldn't a try-catch block catch the exception th...

# javascript

[Mihai Voicescu]

Shouldn't a try-catch block catch the exception throw by awaiting a Promise?

try {
            val p = window.navigator.mediaDevices.asDynamic()
                .getDisplayMedia() as Promise<MediaStream>
            console.log(p)
            p.await()
        } catch (e: Exception) {
            console.error("Everything is fine")
            console.error(e)
        }

[Mihai Voicescu]

After looking into the generated Javascript code the problem is clear: catch (e:Exception) also checks that the thrown exception is type Exception .

JS errors are not, so catching JS exceptions requires catch (e: Throwable) .

[John Coleman]

I'd be concerned the code above swallows exceptions rather than handling them.

[Mihai Voicescu]

Note that, as Throwable == Error in JavaScript, this does not fix all errors as people can throw other data types, such as strings (for some reason...)

[Mihai Voicescu]

@John Coleman it was just an example, don't worry 😄 .