harper_core/expr/
first_match_of.rs

1use super::{AsBoxedExpr, Expr};
2use crate::{Span, Token};
3
4/// A naive expr collection that naively iterates through a list of patterns,
5/// returning the first one that matches.
6///
7/// Compare to [`LongestMatchOf`](super::LongestMatchOf), which returns the longest match.
8#[derive(Default)]
9pub struct FirstMatchOf {
10    exprs: Vec<Box<dyn Expr>>,
11}
12
13impl FirstMatchOf {
14    pub fn new(exprs: impl IntoIterator<Item = impl AsBoxedExpr>) -> Self {
15        Self {
16            exprs: exprs.into_iter().map(|e| e.into_boxed_expr()).collect(),
17        }
18    }
19
20    pub fn add(&mut self, expr: impl Expr + 'static) {
21        self.exprs.push(Box::new(expr));
22    }
23
24    pub fn add_boxed(&mut self, expr: Box<dyn Expr>) {
25        self.exprs.push(expr);
26    }
27}
28
29impl Expr for FirstMatchOf {
30    fn run(&self, cursor: usize, tokens: &[Token], source: &[char]) -> Option<Span<Token>> {
31        self.exprs
32            .iter()
33            .find_map(|p| p.run(cursor, tokens, source))
34    }
35}
harper_core/expr/first_match_of.rs

harper_core/expr/
first_match_of.rs
