mirror of
https://github.com/haraldh/chainerror.git
synced 2024-10-05 12:15:10 +02:00
53 lines
1.2 KiB
Rust
53 lines
1.2 KiB
Rust
|
/*!
|
||
|
|
||
|
~~~bash
|
||
|
$ cargo run -q --example tutorial6
|
||
|
Error: func1 error
|
||
|
caused by: Error reading 'foo.txt'
|
||
|
caused by: std::io::Error: entity not found
|
||
|
of kind: std::io::ErrorKind::NotFound
|
||
|
~~~
|
||
|
|
||
|
!*/
|
||
|
|
||
|
use chainerror::prelude::*;
|
||
|
use std::error::Error;
|
||
|
use std::io;
|
||
|
use std::result::Result;
|
||
|
|
||
|
fn do_some_io() -> Result<(), Box<Error>> {
|
||
|
Err(io::Error::from(io::ErrorKind::NotFound))?;
|
||
|
Ok(())
|
||
|
}
|
||
|
|
||
|
fn func2() -> Result<(), Box<Error>> {
|
||
|
let filename = "foo.txt";
|
||
|
do_some_io().map_err(mstrerr!("Error reading '{}'", filename))?;
|
||
|
Ok(())
|
||
|
}
|
||
|
|
||
|
fn func1() -> Result<(), Box<Error>> {
|
||
|
func2().map_err(mstrerr!("func1 error"))?;
|
||
|
Ok(())
|
||
|
}
|
||
|
|
||
|
fn main() -> Result<(), Box<Error>> {
|
||
|
if let Err(e) = func1() {
|
||
|
eprintln!("Error: {}", e);
|
||
|
let mut s = e.as_ref();
|
||
|
while let Some(c) = s.source() {
|
||
|
if let Some(ioerror) = c.downcast_ref::<io::Error>() {
|
||
|
eprintln!("caused by: std::io::Error: {}", ioerror);
|
||
|
match ioerror.kind() {
|
||
|
io::ErrorKind::NotFound => eprintln!("of kind: std::io::ErrorKind::NotFound"),
|
||
|
_ => {}
|
||
|
}
|
||
|
} else {
|
||
|
eprintln!("caused by: {}", c);
|
||
|
}
|
||
|
s = c;
|
||
|
}
|
||
|
}
|
||
|
Ok(())
|
||
|
}
|