# error_hook_attr
This library supplements `hook` _macro attribute_ to hook error conversion
(please use the re-exported macro from `error_hook` via feature `attribute`).
## Example
```rust
use error_hook::{self, hook};
#[hook(e => tracing::error!("{e}"))] // <-
#[tracing::instrument]
async fn test(a: i32, b: i32) -> error_hook::Result<i32> {
a.checked_mul(b).ok_or(anyhow::anyhow!("overflow"))
}
#[tokio::main]
async fn main() -> anyhow::Result<()> {
tracing_subscriber::fmt()
.with_max_level(tracing::Level::INFO)
.init();
let ans = test(888888888, 888888888).await?;
println!("{ans}");
Ok(())
}
```
output
```shell
2023-03-04T06:23:33.048087Z ERROR test{a=888888888 b=888888888}: example: overflow
```