Reid/src/errors.rs

58 lines
1.6 KiB
Rust

use super::parser::Position;
use std::fmt;
use std::fmt::Display;
use std::io;
#[derive(Debug)]
pub enum GenericError {
StdIOError(io::Error),
}
impl From<io::Error> for GenericError {
fn from(error: io::Error) -> Self {
Self::StdIOError(error)
}
}
#[derive(Debug)]
pub enum CompilerError {
Fatal,
ExpectedToken(Position, char),
ExpectedExpression(Position, Option<Box<CompilerError>>),
ExpectedIdent(Position),
ExpectedStatement(Position, Option<Box<CompilerError>>),
ExpectedPattern(Position),
}
impl CompilerError {
fn from_opt(from: &Option<Box<CompilerError>>) -> String {
if let Some(err) = from {
format!("\n {}", err)
} else {
String::new()
}
}
}
impl Display for CompilerError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let text = match self {
CompilerError::Fatal => "Fatal error".to_string(),
CompilerError::ExpectedToken(pos, c) => format!("Expected token '{}' at {}", c, pos),
CompilerError::ExpectedExpression(pos, err) => format!(
"Expected expression at {}{}",
pos,
CompilerError::from_opt(err)
),
CompilerError::ExpectedIdent(pos) => format!("Expected ident at {}", pos),
CompilerError::ExpectedStatement(pos, err) => format!(
"Expected statement at {}{}",
pos,
CompilerError::from_opt(err)
),
CompilerError::ExpectedPattern(pos) => format!("Expected pattern at {}", pos),
};
write!(f, "{}", text)
}
}