use std::fmt::{self, Debug, Display, Formatter};
pub struct Error {
msg: String,
}
impl Error {
pub fn new<M: Into<String>>(msg: M) -> Self {
Error { msg: msg.into() }
}
}
impl Display for Error {
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
write!(f, "{}", self.msg)
}
}
impl Debug for Error {
fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
write!(f, "{}", self.msg)
}
}
impl std::error::Error for Error {
fn description(&self) -> &str {
self.msg.as_str()
}
}
pub trait ErrorExt {
fn wrap(self) -> Error;
fn context<C: Display + Send + Sync + 'static>(self, ctx: C) -> Error;
}
impl<E: std::error::Error + Send + Sync + 'static> ErrorExt for E {
fn wrap(self) -> Error {
Error { msg: self.to_string() }
}
fn context<C: Display + Send + Sync + 'static>(self, ctx: C) -> Error {
let msg = format!("{}: {}", ctx, self.to_string());
Error { msg }
}
}
pub trait ResultExt<T> {
fn wrap(self) -> Result<T, Error>;
fn context<C: Display + Send + Sync + 'static>(self, ctx: C) -> Result<T, Error>;
}
impl<T, E: std::error::Error + Send + Sync + 'static> ResultExt<T> for Result<T, E> {
fn wrap(self) -> Result<T, Error> {
self.map_err(|e| e.wrap())
}
fn context<C: Display + Send + Sync + 'static>(self, ctx: C) -> Result<T, Error> {
self.map_err(|e| e.context(ctx))
}
}