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An unstable `std::backtrace::Backtrace` (https://doc.rust-lang.org/nightly/std/backtrace/struct.Backt...) exists in nightly Rust. If you cannot require nightly, you can use the backtrace crate (https://docs.rs/backtrace/0.3.40/backtrace/) on stable.

Crates like my SNAFU (https://docs.rs/snafu/0.6.0/snafu/) help abstract this away. Whenever the standard library implementation stabilizes, you will likely see many more errors including backtraces.

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Are you familiar with how costly backtrace is?

I fear bubbling an error up and repeatedly adding a stack trace or some junk like that. Admittedly I have not looked too much into Backtrace, but I hope my concern makes sense.

I do believe it's non-zero, as the stack has to be walked and potentially symbols are looked up. The symbols can be delayed until display time, but the stalk walk is "now or never", as I understand it.

SNAFU addresses this by allowing `Option<Backtrace>` in the error struct. The backtrace is only captured when an environment variable is set by the end user.

It would be interesting for someone to port the Linux kernel’s ORC to user code. ORC backtraces are exact and more than an order of magnitude faster than DWARF.

> Are you familiar with how costly...

Checks the username of who you responded too: I'll blindly bet yes to that question for any amount you desire.

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