use std::error::Error;
use std::fmt;
#[derive(Debug)]
pub struct AutoDiffError {
details: String
}
impl AutoDiffError {
pub fn new(msg: &str) -> AutoDiffError {
AutoDiffError{
details: msg.to_string()
}
}
}
impl fmt::Display for AutoDiffError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f,"{}",self.details)
}
}
impl Error for AutoDiffError {
fn description(&self) -> &str {
&self.details
}
}
impl From<AutoDiffError> for std::fmt::Error {
fn from(item: AutoDiffError) -> std::fmt::Error {
std::fmt::Error::default()
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test() {
fn return_err() -> Result<(), AutoDiffError> {
Err(AutoDiffError::new(&format!("{:?}", 12)))
}
let e = return_err();
assert!(e.is_err());
}
}