pegtastic_runtime/
lib.rs

1use std::fmt::Display;
2
3pub mod str;
4mod slice;
5pub mod error;
6
7/// The result type used internally in the parser.
8/// 
9/// You'll only need this if implementing the `Parse*` traits for a custom input
10/// type. The public API of a parser adapts errors to `std::result::Result`.
11#[derive(Clone, PartialEq, PartialOrd, Eq, Ord, Debug, Hash)]
12pub enum RuleResult<T> {
13    Matched(usize, T),
14    Failed,
15}
16
17/// A type that can be used as input to a parser.
18pub trait Parse {
19    type PositionRepr: Display;
20    fn start<'input>(&'input self) -> usize;
21    fn position_repr<'input>(&'input self, p: usize) -> Self::PositionRepr;
22}
23
24/// A parser input type supporting the `[...]` syntax.
25pub trait ParseElem: Parse {
26    /// Type of a single atomic element of the input, for example a character or token
27    type Element;
28
29    /// Get the element at `pos`, or `Failed` if past end of input.
30    fn parse_elem(&self, pos: usize) -> RuleResult<Self::Element>;
31}
32
33/// A parser input type supporting the `"literal"` syntax.
34pub trait ParseLiteral: Parse {
35    /// Attempt to match the `literal` string at `pos`, returning whether it
36    /// matched or failed.
37    fn parse_string_literal(&self, pos: usize, literal: &str) -> RuleResult<()>;
38}
39
40/// A parser input type supporting the `$()` syntax.
41pub trait ParseSlice<'input>: Parse {
42    /// Type of a slice of the input.
43    type Slice;
44
45    /// Get a slice of input.
46    fn parse_slice(&'input self, p1: usize, p2: usize) -> Self::Slice;
47}
48
pegtastic_runtime/lib.rs

pegtastic_runtime/
lib.rs
