asciimath/
error.rs

1use std::fmt;
2
3#[derive(PartialEq, Debug)]
4pub enum Error {
5    MissingOperands(String),         // operator
6    NotEnoughFunctionParams(String), // fn name
7    FunctionSyntaxError(String),     // fn name
8    UnknownFunction(String),         // fn name
9    UnknownVariable(String),         // var name
10    CannotEvaluateToken(String),     // invalid token on stack
11    InvalidToken(String),
12    EmptyExpression,
13}
14
15impl fmt::Display for Error {
16    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
17        match self {
18            Error::MissingOperands(operator) => write!(
19                f,
20                "Expected more operands for operator \"{}\"",
21                operator
22            ),
23            Error::NotEnoughFunctionParams(fn_name) => write!(
24                f,
25                "Expected more parameters for function \"{}\"",
26                fn_name
27            ),
28            Error::FunctionSyntaxError(fn_name) => write!(
29                f,
30                "Syntax error in function \"{}()\". Usually this occurs \
31                 because of missing or extra commas.",
32                fn_name
33            ),
34            Error::UnknownFunction(fn_name) => write!(
35                f,
36                "Function\"{}()\" does not exist. If it is a custom function, \
37                 make sure you are passing it through the Scope.",
38                fn_name
39            ),
40            Error::UnknownVariable(var_name) => write!(
41                f,
42                "Variable \"{}\" is not defined. Make sure you are passing it \
43                 through the Scope.",
44                var_name
45            ),
46            Error::CannotEvaluateToken(token) => write!(
47                f,
48                "Token \"{}\" does not belong on the stack. Please open an \
49                 issue with your expression at \
50                 https://github.com/chmln/asciimath-rs/issues",
51                token
52            ),
53            Error::InvalidToken(token) => {
54                write!(f, "Invalid token: \"{}\"", token)
55            },
56            Error::EmptyExpression => write!(
57                f,
58                "The expression is empty and there is nothing to evaluate"
59            ),
60        }
61    }
62}
63
64impl std::error::Error for Error {}
asciimath/error.rs

asciimath/
error.rs
