Struct Error 

pub struct Error {
    pub error: ErrorType,
    pub line: usize,
}

The Error struct represents an error that occurred during parsing or execution, with the line number denoting its position.

Usually, you’ll only need this struct in a function signature to propagate errors. To construct an Error manually, provide an ErrorType and a line number. Alternatively, you can call with_line on an ErrorType enum variant.

Example

Accessing error information

use castwright::{Error, ErrorType};

let error_type = ErrorType::UnknownInstruction;
let error = error_type.with_line(1);
assert!(matches!(error.error, ErrorType::UnknownInstruction));
assert_eq!(error.line, 1);

Propagating an error in fn main

use castwright::{CastWright, Error};
use std::io::BufReader;

fn main() -> Result<(), Error> {
    let text = r#"
        $ unexpected
        > continuation
    "#;
    let text = text.trim();
    let mut reader = BufReader::new(text.as_bytes());
    let mut stdout = std::io::stdout().lock();
    let castwright = CastWright::new();
    castwright.run(&mut reader, &mut stdout)?;
    Ok(())
}
// Should get the following output:
// Error: Error { error: UnexpectedContinuation, line: 2 }

Constructing an Error manually

use castwright::{Error, ErrorType};

fn main() -> Result<(), Error> {
    let error_type = ErrorType::UnknownInstruction;
    let error = error_type.with_line(1);
    // Or:
    // let error = Error {
    //     error: ErrorType::UnknownInstruction,
    //     line: 1,
    // };
    Err(error)
}
// Should get the following output:
// Error: Error { error: UnknownInstruction, line: 1 }

Fields

error: ErrorType

The type of error that occurred.

line: usize

The line number where the error occurred, starting at 1. If 0, the error is not related to a specific line.

Trait Implementations

impl Debug for Error

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Error

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for Error

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.