No way to re-throw errors with a stack trace

[nex3]

When working with asynchronous code, and Futures in particular, you often end up with an exception object and its stack trace outside of the catch block where the exception was originally caught. Currently, there's no way to throw that exception so that when it's caught, the catcher sees the original stack trace rather than the trace of where the exception is re-thrown.

This is one of several issues that makes it extremely difficult to debug asynchronous code in Dart.

[nex3]

Issue #2763 has been merged into this issue.

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cc @sigmundch.

[gbracha]

Added Duplicate label.
Marked as being merged into #4046.

[gbracha]

Marked as being merged into #4061.

[DartBot]

This comment was originally written by zh...@gmail.com

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Do we have a reason why it is bad to include the getStackTrace() method on Exception object? I agree that debugging heavy async code in dart is not fun at all.

[nex3]

I believe the idea is that it's expensive to gather the stack trace for an exception, and that gathering must happen when the exception is thrown. Declaring in the catch clause whether a stack trace is needed allows it to only be collected when necessary.

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Marked as being merged into #4061.