28 lines
939 B
Rust
28 lines
939 B
Rust
use crate::{error_handling::SyntaxError, lexic::token::Token};
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/// The result of a parsing operation.
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/// On success, it contains the item and the position of the next token
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/// On failure, it contains the error
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pub type ParsingResult<'a, A> = Result<(A, usize), ParsingError<'a>>;
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#[derive(Debug)]
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pub enum ParsingError<'a> {
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/// The parsing didn't succeed, but it's not a fatal error
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Unmatched,
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/// Some other token was found than the expected one
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Mismatch(&'a Token),
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/// The parsing failed past a point of no return.
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///
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/// For example, when parsing a function declaration
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/// the `fun` token is found, but then no identifier
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Err(SyntaxError),
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}
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/// Represents a type that can be parsed using Recursive Descent
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pub trait Parseable<'a> {
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type Item;
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/// Try to parse the current production.
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fn try_parse(tokens: &'a Vec<Token>, current_pos: usize) -> ParsingResult<'a, Self::Item>;
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}
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