use std::{
error,
fmt::{self, Display},
io,
};
use scroll;
#[derive(Debug)]
pub enum Error {
MalFormed(String),
IO(io::Error),
InvalidId(String),
Scroll(scroll::Error),
BadOffset(usize, String),
}
impl error::Error for Error {
fn description(&self) -> &str {
match *self {
Error::IO(_) => "IO error",
Error::MalFormed(_) => "Entity is malformed in some way",
Error::Scroll(_) => "Scroll error",
Error::InvalidId(_) => "Invalid index",
Error::BadOffset(_, _) => "Invalid offset",
}
}
fn cause(&self) -> Option<&error::Error> {
match *self {
Error::IO(ref io) => io.source(),
Error::Scroll(ref err) => err.source(),
Error::MalFormed(_) => None,
Error::InvalidId(_) => None,
Error::BadOffset(_, _) => None,
}
}
}
impl From<io::Error> for Error {
fn from(err: io::Error) -> Error {
Error::IO(err)
}
}
impl From<scroll::Error> for Error {
fn from(err: scroll::Error) -> Error {
Error::Scroll(err)
}
}
impl Display for Error {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
match *self {
Error::IO(ref err) => write!(fmt, "{}", err),
Error::Scroll(ref err) => write!(fmt, "{}", err),
Error::MalFormed(ref msg) => write!(fmt, "Malformed entity: {}", msg),
Error::InvalidId(ref msg) => write!(fmt, "{}", msg),
Error::BadOffset(offset, ref msg) => write!(fmt, "{}: {}", msg, offset),
}
}
}