use crate::bnf::Bnf;
use crate::parser::{ParseResult, Parser, ParserInput};

pub struct BoxedParser<'a, I, O, E>
where
    I: ParserInput,
{
    inner: Box<dyn Parser<I, O, E> + 'a>,
}

impl<'a, I, O, E> BoxedParser<'a, I, O, E>
where
    I: ParserInput,
{
    pub(crate) fn new<P>(inner: P) -> Self
    where
        P: Parser<I, O, E> + 'a,
    {
        BoxedParser {
            inner: Box::new(inner),
        }
    }
}

impl<'a, I: ParserInput, O, E> Parser<I, O, E> for BoxedParser<'a, I, O, E> {
    fn parse(&self, input: I) -> ParseResult<I, O, E> {
        self.inner.parse(input)
    }

    fn bnf(&self) -> Option<Bnf> {
        self.inner.bnf()
    }
}