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

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

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

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.