Anywrap

Anywrap is an error handler designed for applications, similar to anyhow, but it supports matching on enum variants, making it more ergonomic.

Example

use std::fmt;
use std::fs::File;
use anywrap::{anywrap, AnyWrap};

pub struct ErrorCode(pub u32);

impl fmt::Display for ErrorCode {
   fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
      write!(f, "{}", self.0)
   }
}

#[derive(AnyWrap)]
#[anywrap]
pub enum Error {
   #[anywrap_attr(display = "Error Code: {code}", from = "code")]
   Code { code: ErrorCode },
   #[anywrap_attr(display = "{source}")]
   IO { source: std::io::Error },
}

pub type Result<T, E = Error> = std::result::Result<T, E>;

pub fn define_error() -> Result<()> {
   let e = Error::from(ErrorCode(1));
   Err(e)
}

pub fn chain1() -> Result<()> {
   define_error().context("chain1")
}

pub fn with_chain() -> Result<()> {
   chain1().context("with_chain")
}

pub fn auto() -> Result<()> {
   let _ = File::open("test.txt")?;

   Ok(())
}

fn main() {
   if let Err(e) = auto() {
      println!("--12: {e:?}");
   }
   if let Err(e) = with_chain() {
      println!("--15 display: {e}");
      println!("--15 debug: {e:?}");
   }
}

Output:

--12: No such file or directory (os error 2)
0: No such file or directory (os error 2), at hello-anywrap/src/main.rs:38:13

--15 display: Error Code: 1

--15 debug: Error Code: 1
0: Error Code: 1, at hello-anywrap/src/main.rs:13:10
1: chain1, at hello-anywrap/src/main.rs:30:20
2: with_chain, at hello-anywrap/src/main.rs:34:14

Or refer to: full example