vendor/fst/src/error.rs

   1 use std::fmt;
   2 use std::io;
   3
   4 use crate::raw;
   5
   6 /// A `Result` type alias for this crate's `Error` type.
   7 pub type Result<T> = std::result::Result<T, Error>;
   8
   9 /// An error that encapsulates all possible errors in this crate.
  10 #[derive(Debug)]
  11 pub enum Error {
  12     /// An error that occurred while reading or writing a finite state
  13     /// transducer.
  14     Fst(raw::Error),
  15     /// An IO error that occurred while writing a finite state transducer.
  16     Io(io::Error),
  17 }
  18
  19 impl From<io::Error> for Error {
  20     #[inline]
  21     fn from(err: io::Error) -> Error {
  22         Error::Io(err)
  23     }
  24 }
  25
  26 impl From<raw::Error> for Error {
  27     #[inline]
  28     fn from(err: raw::Error) -> Error {
  29         Error::Fst(err)
  30     }
  31 }
  32
  33 impl fmt::Display for Error {
  34     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
  35         match *self {
  36             Error::Fst(_) => write!(f, "FST error"),
  37             Error::Io(_) => write!(f, "I/O error"),
  38         }
  39     }
  40 }
  41
  42 impl std::error::Error for Error {
  43     fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
  44         match *self {
  45             Error::Fst(ref err) => Some(err),
  46             Error::Io(ref err) => Some(err),
  47         }
  48     }
  49 }