String error type.

This crate contains a type StringError, to be used to report top-level errors to a user, such as in a binary when executing main.

Examples

use std::{io::Read, error::Error};

use string_err::{StringError, ResultExt};

pub fn main() -> Result<(), StringError<Box<dyn Error>>> {
	let mut file = std::fs::File::open("README.md")
		.map_err_msg("Could not open the file")?;
	
	let mut contents = String::new();
	file.read_to_string(&mut contents)
		.map_err_msg("Could not read the file")?;
	
	assert!( contents.starts_with("String error type.") );
	
	// ... Do something with `num`
	
	Ok(())
}

This example attempts to load the README.md file, read it and make sure it starts with the string "String error type." (which this readme does).

See the documentation for more details on how to use the StringError type

lib.rs:

String error type

This crate provides a string error type, StringError that may have an underlying error and backtrace too. This is useful for binaries, that need only to display the top-level error to the user and not describe it in code, using an enum.

It may also be used as the return type in main, provided the underlying error type is specified as Box<dyn Error + 'static>

This crate currently uses various nightly features to implement the string error type. Even when the used features are stabilized, this crate will likely keep using other nightly features, as the crate is intended for usage with only binaries. The binaries themselves can use nightly easily, without affecting the libraries built along-side them.