# Playground - Exn Context aware errors. https://github.com/fast/exn https://fast.github.io/blog/stop-forwarding-errors-start-designing-them/ example output: ``` the program died, at src/main.rs:35:34 | |-> failed to create file: res/foo.txt, at src/main.rs:79:43 | |-> Permission denied (os error 13), at src/main.rs:79:43 ```