lexerus/
error.rs

1use std::fmt::Debug;
2
3use super::*;
4
5#[derive(Debug)]
6/// Information about the error which occured when the
7/// [Lexer::lex] failed.
8pub struct Error<'code> {
9    pub buffer: Buffer<'code>,
10    /// This is included not just for debug information,
11    /// but also to allow [lexerus_derive::Lexer]
12    /// to obtain some basic information about how many
13    /// tokens were matched before the program
14    /// failed. This is useful when debugging `enum`
15    /// because it would not be immediately obvious
16    /// which match pattern failed.
17    pub matched: usize,
18    pub kind: Kind,
19}
20
21impl<'code> ::std::fmt::Display for Error<'code> {
22    fn fmt(
23        &self,
24        f: &mut std::fmt::Formatter<'_>,
25    ) -> std::fmt::Result {
26        ::std::fmt::Debug::fmt(&self, f)
27    }
28}
29
30#[cfg(test)]
31impl<'code> ::std::error::Error for Error<'code> {}
32
33#[derive(Debug, PartialEq, Eq)]
34/// Describes the type of error found.
35pub enum Kind {
36    /// This means that the token was not found
37    NotFound(&'static str),
38    /// This means that an unexpected token was encountered.
39    UnexpectedToken(&'static str),
40}
lexerus/error.rs

lexerus/
error.rs
