system2 0.1.0

An (unofficial) idiomatic Rust SDK for TypeSafe's System One model, Jev.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77

use crate::{
    AskError, CacheError, EnvError, InvalidAnswer, InvalidBbox, InvalidChoice, InvalidImage,
    InvalidNoul, InvalidScore, QuestionError,
};
use std::fmt;

/// Each error of the crate.
///
/// Each error type converts into it, so `?` works in a function that returns [`Result`].
/// [`InvalidJson`](crate::InvalidJson) is only a part of another error, so it does not convert.
///
/// Its `Debug` output is the message and its causes, so a `main` that returns [`Result`] prints
/// the fix, not the name of a variant. Match on the variants to tell the errors apart.
#[derive(thiserror::Error)]
#[non_exhaustive]
pub enum Error {
    /// A constructor refused a question.
    #[error(transparent)]
    Question(#[from] QuestionError),
    /// An answer that a test built breaks a rule of its question.
    #[error(transparent)]
    Answer(#[from] InvalidAnswer),
    /// An image breaks a rule of [`Image`](crate::Image).
    #[error(transparent)]
    Image(#[from] InvalidImage),
    /// A request failed.
    #[error(transparent)]
    Ask(#[from] AskError),
    /// The client cannot read or write the cache file.
    #[error(transparent)]
    Cache(#[from] CacheError),
    /// A variable of the environment has a bad value.
    #[error(transparent)]
    Env(#[from] EnvError),
}

impl fmt::Debug for Error {
    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(formatter, "{self}")?;
        let mut source = std::error::Error::source(self);
        if source.is_some() {
            write!(formatter, "\n\nCaused by:")?;
        }
        while let Some(cause) = source {
            write!(formatter, "\n    {cause}")?;
            source = cause.source();
        }
        Ok(())
    }
}

impl From<InvalidNoul> for Error {
    fn from(error: InvalidNoul) -> Self {
        Error::Question(QuestionError::Noul(error))
    }
}

impl From<InvalidChoice> for Error {
    fn from(error: InvalidChoice) -> Self {
        Error::Question(QuestionError::Choice(error))
    }
}

impl From<InvalidScore> for Error {
    fn from(error: InvalidScore) -> Self {
        Error::Question(QuestionError::Score(error))
    }
}

impl From<InvalidBbox> for Error {
    fn from(error: InvalidBbox) -> Self {
        Error::Question(QuestionError::Bbox(error))
    }
}

/// A `Result` with [`Error`] as its default error.
pub type Result<T, E = Error> = std::result::Result<T, E>;