2018-12-20 16:37:08 +01:00
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# Downcast the Errors
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2018-12-20 15:14:21 +01:00
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2018-12-21 13:50:08 +01:00
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`std::error::Error` comes with some helper methods to get to the original object of the
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`&(dyn Error + 'static)` returned by `.source()`.
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~~~rust,ignore
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pub fn downcast_ref<T: Error + 'static>(&self) -> Option<&T>
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pub fn downcast_mut<T: Error + 'static>(&mut self) -> Option<&mut T>
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~~~
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This is how it looks like, when using those:
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2018-12-20 15:14:21 +01:00
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2018-12-20 14:52:06 +01:00
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~~~rust
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2019-03-04 11:38:35 +01:00
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{{#include ../examples/tutorial6.rs}}
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2018-12-20 14:52:06 +01:00
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# #[allow(dead_code)]
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# mod chainerror {
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{{#includecomment ../src/lib.rs}}
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# }
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~~~
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