use std::convert::Infallible;
use std::error::Error as StdError;
use std::fmt;
type BoxError = Box<dyn std::error::Error + Send + Sync>;
pub struct Error {
inner: BoxError,
}
impl Error {
pub(crate) fn new<E: Into<BoxError>>(err: E) -> Error {
Error { inner: err.into() }
}
}
impl fmt::Debug for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
fmt::Debug::fmt(&self.inner, f)
}
}
impl fmt::Display for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
fmt::Display::fmt(&self.inner, f)
}
}
impl StdError for Error {}
impl From<Infallible> for Error {
fn from(infallible: Infallible) -> Error {
match infallible {}
}
}
#[test]
fn error_size_of() {
assert_eq!(
::std::mem::size_of::<Error>(),
::std::mem::size_of::<usize>() * 2
);
}
macro_rules! unit_error {
(
$(#[$docs:meta])*
$pub:vis $typ:ident: $display:literal
) => (
$(#[$docs])*
$pub struct $typ { _p: (), }
impl ::std::fmt::Debug for $typ {
fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
f.debug_struct(stringify!($typ)).finish()
}
}
impl ::std::fmt::Display for $typ {
fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
f.write_str($display)
}
}
impl ::std::error::Error for $typ {}
)
}