exitfailure 0.5.1

A basic newtype wrappers for use with ? in main
Documentation

exitfailure - convenient newtype wrappers for using ? in main()

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exitfailure provides some newtype wrappers to help with using ? in main().

It is intended to be used with rust 1.26 and above's "? in main()" feature (see the tracking issue here).

The primary items exported by this library are:

  • ExitFailure: a wrapper around failure::Error to allow ? printing from main to present a nicer error message, including any available context and backtrace.

  • ExitDisplay<E>: a wrapper around E: std::fmt::Display to allow the error message from main to use Display and not Debug.

For more information, including more details on the types, please see the API Documentation.

Example:

#[macro use] extern crate failure;
extern crate exitfailure;

use failure::ResultExt;
use exitfailure::ExitFailure;

fn main() -> Result<(), ExitFailure> {
     Ok(some_fn()?)
}

fn some_fn() -> Result<(), failure::Error> {
     let error = Err(failure::err_msg("root cause failure"));
     Ok(error.context("this is some context".to_string())?)
}

This will print, when executed:

Error: this is some context
Info: caused by root cause failure

If the environment variable RUST_BACKTRACE=1 is set, then the printing will include whatever backtrace information is provided by the failure::Error that is being wrapped.

License

Licensed under either of

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.