use std::fmt;
#[derive(Clone,Copy,PartialEq)]
pub struct ErrorPos {
#[allow(missing_docs)]
pub row: usize,
#[allow(missing_docs)]
pub col: usize,
}
impl ErrorPos {
pub fn new(row: usize, col: usize) -> ErrorPos {
ErrorPos {
row: row,
col: col,
}
}
}
impl fmt::Debug for ErrorPos {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}:{}", &self.row, &self.col)
}
}
#[derive(Clone,Copy,PartialEq)]
pub enum Error {
UnexpectedEndOfStream(ErrorPos),
InvalidAdvance {
expected: isize,
total: usize,
pos: ErrorPos,
},
UnsupportedToken(ErrorPos),
UnknownToken(ErrorPos),
}
impl fmt::Debug for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match *self {
Error::UnexpectedEndOfStream(ref pos) =>
write!(f, "Unexpected end of stream at {:?}", pos),
Error::InvalidAdvance{ref expected, ref total, ref pos} =>
write!(f, "Attempt to advance to the pos {} from {:?}, but total len is {}",
expected, pos, total),
Error::UnsupportedToken(ref pos) =>
write!(f, "Unsupported token at {:?}", pos),
Error::UnknownToken(ref pos) =>
write!(f, "Unknown token at {:?}", pos),
}
}
}