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use crate::scanner::ScannerError;
use crate::treewalk::interpreter::Value;
use std::fmt;
#[derive(Debug)]
pub enum ErrorKind {
UnexpectedChar(char),
UnterminatedString,
UnmatchedParens,
ExpectedExpression(String),
ExpectedSemicolon,
ExpectedClosingBrace,
ExpectedToken(&'static str),
TypeError(String),
UndefinedVariable(String),
InternalError(String),
InvalidAssignmentTarget(String),
RuntimeError(String),
StaticError(String),
// This variant is not an error, rather it is used for
// short-circuiting out of a function body that hits a `return`
// statement.
//
// It's implemented this way because in the original book the
// author uses exceptions for control flow, and this is the
// closest equivalent that I had available without diverging too
// much.
FunctionReturn(Value),
}
#[derive(Debug)]
pub struct Error {
pub line: usize,
pub kind: ErrorKind,
}
impl fmt::Display for Error {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "[line {}] Error: {:?}", self.line, self.kind)
}
}
impl From<ScannerError> for Error {
fn from(err: ScannerError) -> Self {
match err {
ScannerError::UnexpectedChar { line, unexpected } => Error {
line,
kind: ErrorKind::UnexpectedChar(unexpected),
},
ScannerError::UnterminatedString { line } => Error {
line,
kind: ErrorKind::UnterminatedString,
},
}
}
}
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