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use crate::{eyre, Buffer, Parse};
#[derive(Debug, Copy, Clone, PartialEq)]
pub struct OneOf<const BYTES: &'static [u8]>(u8);
impl<const BYTES: &'static [u8]> From<OneOf<BYTES>> for u8 {
fn from(v: OneOf<BYTES>) -> Self {
v.0
}
}
impl<const BYTES: &'static [u8]> Parse<u8> for OneOf<BYTES> {
fn parse(input: &mut impl Buffer<u8>) -> eyre::Result<Self> {
match input.next() {
Some(c) => {
if BYTES.contains(&c) {
Ok(Self(c))
} else {
Err(eyre::eyre!(
"error parsing one of {:?}, found {:?}",
BYTES,
c
))
}
}
None => Err(eyre::eyre!("error parsing one of {:?}, reached EOF", BYTES)),
}
}
fn peek(input: &mut impl Buffer<u8>) -> bool {
match input.next() {
Some(c) => BYTES.contains(&c),
None => false,
}
}
}