parol 4.5.0

LL(k) and LALR(1) parser generator for Rust
Documentation 
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use crate::{Pr, Symbol};
use std::fmt::{Display, Error, Formatter};

///
/// Symbol strings are special collections of [Symbol]s.
/// They only contain symbol kinds relevant for operations on grammars.
/// Especially in contrast to [crate::Rhs] of [Pr] productions they don't contain scanner state
/// instructions like %sc, %push and %pop.
///
#[derive(Debug, Clone, Default, Hash, Eq, PartialEq, Ord, PartialOrd)]
pub(crate) struct SymbolString(pub Vec<Symbol>);

impl From<&Pr> for SymbolString {
    fn from(pr: &Pr) -> Self {
        Self(
            pr.get_r()
                .iter()
                .fold(Vec::with_capacity(pr.len()), |mut acc, e| {
                    acc.push(e.clone());
                    acc
                }),
        )
    }
}

impl Display for SymbolString {
    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error> {
        write!(
            f,
            "{}",
            self.0
                .iter()
                .map(|e| format!("{e}"))
                .collect::<Vec<String>>()
                .join(", ")
        )
    }
}