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mod tag;
pub use tag::*;
mod one_of;
pub use one_of::*;
mod many;
pub use many::*;
use crate::{eyre, Buffer, Parse};
#[derive(Debug, Copy, Clone, PartialEq)]
pub struct LineEnding;
impl Parse<char> for LineEnding {
fn parse(input: &mut impl Buffer<char>) -> eyre::Result<Self> {
match Self::peek(input) {
true => Ok(Self),
false => Err(eyre::eyre!("could not parse line ending")),
}
}
fn peek(input: &mut impl Buffer<char>) -> bool {
match input.next() {
Some('\n') => true,
Some('\r') => input.next() == Some('\n'),
_ => false,
}
}
}
#[derive(Debug, Copy, Clone, PartialEq)]
pub struct Space;
impl Parse<char> for Space {
fn parse(input: &mut impl Buffer<char>) -> eyre::Result<Self> {
match Self::peek(input) {
true => Ok(Self),
false => Err(eyre::eyre!("could not parse space")),
}
}
fn peek(input: &mut impl Buffer<char>) -> bool {
matches!(input.next(), Some(' ') | Some('\t'))
}
}
#[derive(Debug, Copy, Clone, PartialEq)]
pub struct WhiteSpace;
impl Parse<char> for WhiteSpace {
fn parse(input: &mut impl Buffer<char>) -> eyre::Result<Self> {
match Self::peek(input) {
true => Ok(Self),
false => Err(eyre::eyre!("could not parse whitespace")),
}
}
fn peek(input: &mut impl Buffer<char>) -> bool {
match input.next() {
Some(' ') | Some('\t') | Some('\n') => true,
Some('\r') => input.next() == Some('\n'),
_ => false,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::IntoBuf;
#[test]
fn parse_spaces() {
let mut input = " \t \t \t\t \t.".chars().into_buf();
let output = Vec::<Space>::parse(&mut input).unwrap();
assert_eq!(output.len(), 12);
assert_eq!(input.next(), Some('.'));
}
#[test]
fn peek_spaces() {
let mut input = " \t \t \t\t \t.".chars().into_buf();
let mut cursor = input.cursor();
assert!(Vec::<Space>::peek(&mut cursor));
assert_eq!(cursor.next(), Some('.'));
}
#[test]
fn parse_newline() {
let mut input = "\n.\r\n.".chars().into_buf();
let _ = LineEnding::parse(&mut input).unwrap();
assert_eq!(input.next(), Some('.'));
let _ = LineEnding::parse(&mut input).unwrap();
assert_eq!(input.next(), Some('.'));
}
}