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-rw-r--r--src/nibble/parse/iter.rs149
-rw-r--r--src/nibble/parse/mod.rs61
2 files changed, 0 insertions, 210 deletions
diff --git a/src/nibble/parse/iter.rs b/src/nibble/parse/iter.rs
deleted file mode 100644
index 1c635a3..0000000
--- a/src/nibble/parse/iter.rs
+++ /dev/null
@@ -1,149 +0,0 @@
-use std::iter::Peekable;
-
-pub use self::take_while::PeekableTakeWhile;
-
-/// An iterator with a `peek()` that returns an optional reference to the next
-/// element.
-///
-/// This trait is an extension of the `Peekable` type in the standard library.
-pub trait Peek: Iterator {
- /// Returns a reference to the [`next`] value without advancing the iterator.
- ///
- /// Like [`next`], if there is a value, it is wrapped in [`Some`]. But if
- /// iteration is over, [`None`] is returned.
- fn peek(&mut self) -> Option<&Self::Item>;
-}
-
-impl<I: Peek> Peek for &mut I {
- fn peek(&mut self) -> Option<&Self::Item> {
- I::peek(self)
- }
-}
-
-impl<I> Peek for Box<&mut dyn Peek<Item = I>> {
- fn peek(&mut self) -> Option<&Self::Item> {
- (**self).peek()
- }
-}
-
-impl<I: Iterator> Peek for Peekable<I> {
- fn peek(&mut self) -> Option<&Self::Item> {
- Peekable::peek(self)
- }
-}
-
-pub trait PeekExt: Peek {
- /// Returns the [`next`] value and advance the iterator only if `pred` is true.
- fn next_if<P: FnOnce(&Self::Item) -> bool>(
- &mut self,
- pred: P,
- ) -> Option<Result<Self::Item, &mut Self>> {
- let i = self.peek()?;
-
- if pred(i) {
- Some(Ok(self.next().unwrap()))
- } else {
- Some(Err(self))
- }
- }
-
- fn next_if_then<
- P: FnOnce(&Self::Item) -> bool,
- F: FnOnce(Self::Item) -> T,
- G: FnOnce(&mut Self) -> T,
- T,
- >(
- &mut self,
- pred: P,
- matched: F,
- unmatched: G,
- ) -> Option<T> {
- let i = self.peek()?;
-
- if pred(i) {
- Some(matched(self.next().unwrap()))
- } else {
- Some(unmatched(self))
- }
- }
-
- /// Advances the iterator only if the [`next`] item equals `val`.
- fn next_if_eq<T>(&mut self, val: &T) -> Option<Result<(), &Self::Item>>
- where
- Self::Item: PartialEq<T>,
- {
- self.next_if(|i| PartialEq::eq(i, val))
- .map(|r| r.map(|_| ()).map_err(|i| i.peek().unwrap()))
- }
-
- fn consume_if_next<T>(&mut self, val: &T) -> bool
- where
- Self::Item: PartialEq<T>,
- {
- self.next_if_eq(val).map(|r| r.is_ok()).unwrap_or(false)
- }
-
- /// Advance the iterator until `pred` is false, or `peek` returns [`None`].
- fn advance_while<P: FnMut(&Self::Item) -> bool>(&mut self, mut pred: P) {
- while self.next_if(&mut pred).map(|r| r.is_ok()).unwrap_or(false) {
- // Condition already loops for us
- }
- }
-}
-
-impl<I: Peek> PeekExt for I {}
-
-mod take_while {
- use super::Peek;
-
- #[derive(Clone, Debug, Eq, PartialEq)]
- pub struct PeekableTakeWhile<I, F> {
- inner: I,
- predicate: Option<F>,
- }
-
- impl<I, F> PeekableTakeWhile<I, F>
- where
- I: Peek,
- F: FnMut(&<I as Iterator>::Item) -> bool,
- {
- pub fn new(iter: I, predicate: F) -> Self {
- Self {
- inner: iter,
- predicate: Some(predicate),
- }
- }
- }
-
- impl<I, F> Iterator for PeekableTakeWhile<I, F>
- where
- I: Peek,
- F: FnMut(&<I as Iterator>::Item) -> bool,
- {
- type Item = <I as Iterator>::Item;
-
- fn next(&mut self) -> Option<Self::Item> {
- // Can't inline because of lifetimes
- let inner = &mut self.inner;
- if self.predicate.as_mut().and_then(|p| inner.peek().map(p))? {
- self.inner.next()
- } else {
- self.predicate = None;
- None
- }
- }
- }
-
- impl<I, F> Peek for PeekableTakeWhile<I, F>
- where
- I: Peek,
- F: FnMut(&<I as Iterator>::Item) -> bool,
- {
- fn peek(&mut self) -> Option<&Self::Item> {
- let inner = &mut self.inner;
- self.predicate
- .as_mut()
- .and_then(move |p| inner.peek().filter(|i| p(i)))
- }
- }
-}
diff --git a/src/nibble/parse/mod.rs b/src/nibble/parse/mod.rs
deleted file mode 100644
index 13c4c0e..0000000
--- a/src/nibble/parse/mod.rs
+++ /dev/null
@@ -1,61 +0,0 @@
-pub mod iter;
-
-use self::iter::Peek;
-use self::iter::PeekExt;
-
-#[derive(Clone, Copy, Debug, Eq, PartialEq)]
-pub enum ParseError<E> {
- EndOfFile,
- InvalidCharacter(char),
- Other(E),
-}
-
-impl<U> ParseError<U> {
- pub fn map<T: Into<U>>(other: ParseError<T>) -> Self {
- match other {
- ParseError::EndOfFile => Self::EndOfFile,
- ParseError::InvalidCharacter(c) => Self::InvalidCharacter(c),
- ParseError::Other(t) => Self::Other(t.into())
- }
- }
-}
-
-/// Parse a value from an iterator.
-pub trait Parse: Sized {
- /// The associated error that can be returned from parsing.
- type Err;
- /// Parses `iter` to return a value of this type.
- ///
- /// This method may not reach the end of `iter`. If so, it must not consume any
- /// characters in the stream that do not form part of the value.
- ///
- /// If parsing succeeds, return the value inside [`Ok`]. Otherwise, when the
- /// iterator is ill-formatted, return an error specific to the inside [`Err`].
- /// The error type is specific to the implementation of the trait.
- fn parse<I: PeekExt<Item = char>>(iter: I) -> Result<Self, ParseError<Self::Err>>;
-}
-
-/// Consumes the next item in `iter` if it equals `c`. Otherwise, returns an
-/// appropriate error without advancing the iterator.
-///
-/// # Examples
-/// Basic usage
-/// ```
-/// use chomp::nibble::parse::{requires, Parse, ParseError};
-/// use std::convert::Infallible;
-///
-/// let s = "hello".to_owned();
-/// let mut iter = s.chars().peekable();
-/// assert_eq!(requires::<_, Infallible>(&mut iter, 'h'), Ok(()));
-/// assert_eq!(requires::<_, Infallible>(&mut iter, 'e'), Ok(()));
-/// assert_eq!(requires::<_, Infallible>(&mut iter, 'z'), Err(ParseError::InvalidCharacter('l')));
-/// assert_eq!(iter.next(), Some('l'));
-/// assert_eq!(iter.next(), Some('l'));
-/// assert_eq!(iter.next(), Some('o'));
-/// assert_eq!(requires::<_, Infallible>(iter, '!'), Err(ParseError::EndOfFile));
-/// ```
-pub fn requires<I: Peek<Item = char>, E>(mut iter: I, c: char) -> Result<(), ParseError<E>> {
- iter.next_if_eq(&c)
- .ok_or(ParseError::EndOfFile)?
- .map_err(|&c| ParseError::InvalidCharacter(c))
-}