Trace_Err

是 tracingcrate 的小型扩展，为 core::result::Result<T, E> 和 core::option::Option<T> 提供了一个单一方法。

为 Result 添加了 trace_expect，除了解包/期望 Result 外，还调用了 tracing::error! 宏（如果为 Result::Err）。

为 Option 添加了 trace_expect，除了解包/期望 Option 外，还调用了 tracing::error! 宏（如果为 Option::None）。

无耻地借鉴了 Log_Err crate。

简写为

use tracing::error;

fn something() -> Result<(), &'static str> {Err("there was some problem")}

let msg = "Some message";
something().map_err(|e| tracing::error!("{}: {:?}", msg, e)).expect(msg)

示例

use std::fs::File;
use trace_err::*;

let mut file = File::open("foo.txt").trace_expect("Error creating file");

# Error will be traced with the error! macro
2024-06-12T09:31:23.933299Z ERROR expect: trace-err/lib.rs:87:39: Error creating file: Os { code: 2, kind: NotFound, message: "No such file or directory" }

# Main program panic'ing with same message
thread 'main' panicked at trace-err/lib.rs:87:39:
Error creating file: Os { code: 2, kind: NotFound, message: "No such file or directory" }