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Michael Pfaff 35bb62320f
Removed stable feature(backtrace)
2 months ago
examples Seems good 10 months ago
src Removed stable feature(backtrace) 2 months ago
.gitignore Where was I? 10 months ago
Cargo.toml Seems good 10 months ago Seems good 10 months ago


A seriously contextual error library that focuses on how you got there. Designed to make debugging parser logic easier, how enables you to concisely capture any and all context that could possibly have contributed to an error.

Getting started

Thanks to how's minimal set of public types whose names are all unique from those of most crates (aside from other error handling libraries), you can safely use star imports anywhere you want to use how.

use how::*;

fn main() -> Result<()> {
	Err(How::new("TODO: implement amazing new program"))

[How] intentionally omits a [From] implementation for [std::error::Error] to discourage the creation of [How]s with no caller context. Instead, the [Explain] trait is implemented for all Result1 and provides a convenient context function.

  1. Where E is either [How] or implements [std::error::Error]. Errors that don't implement [std::error::Error] (usually in order to be permitted to implement [From] for any type that implements [std::error::Error]) can only be, are not, and will not be, supported manually. ↩︎