Trait combine::StreamOnce

pub trait StreamOnce {
    type Item: Clone + PartialEq;
    type Range: Clone + PartialEq;
    type Position: Clone + Ord;
    type Error: ParseError<Self::Item, Self::Range, Self::Position>;
    fn uncons<E>(&mut self) -> Result<Self::Item, E>
    where
        E: StreamError<Self::Item, Self::Range>;
}

StreamOnce represents a sequence of items that can be extracted one by one.

Associated Types

type Item: Clone + PartialEq

The type of items which is yielded from this stream.

type Range: Clone + PartialEq

The type of a range of items yielded from this stream. Types which do not a have a way of yielding ranges of items should just use the Self::Item for this type.

type Position: Clone + Ord

Type which represents the position in a stream. Ord is required to allow parsers to determine which of two positions are further ahead.

type Error: ParseError<Self::Item, Self::Range, Self::Position>

Required Methods

fn uncons<E>(&mut self) -> Result<Self::Item, E> where
    E: StreamError<Self::Item, Self::Range>, 

Takes a stream and removes its first item, yielding the item and the rest of the elements. Returns Err if no element could be retrieved.

Implementations on Foreign Types

impl<'a> StreamOnce for &'a str

type Item = char

type Range = &'a str

type Position = PointerOffset

type Error = StringStreamError

fn uncons<E>(&mut self) -> Result<char, E> where
    E: StreamError<Self::Item, Self::Range>, 

impl<'a, T> StreamOnce for &'a [T] where
    T: Clone + PartialEq, 

type Item = T

type Range = &'a [T]

type Position = PointerOffset

type Error = UnexpectedParse

fn uncons<E>(&mut self) -> Result<T, E> where
    E: StreamError<Self::Item, Self::Range>, 

Implementors

• impl<'a, T> StreamOnce for SliceStream<'a, T> where
    T: Clone + PartialEq + 'a,  type Item = &'a T; type Range = &'a [T]; type Position = PointerOffset; type Error = UnexpectedParse;
• impl<I: Iterator> StreamOnce for IteratorStream<I> where
    I::Item: Clone + PartialEq,  type Item = I::Item; type Range = I::Item; type Position = (); type Error = UnexpectedParse;
• impl<R: Read> StreamOnce for ReadStream<R> type Item = u8; type Range = u8; type Position = (); type Error = Error<u8, u8>;
• impl<I, X, S> StreamOnce for State<I, X> where
    I: StreamOnce,
    X: Positioner<I::Item>,
    S: StreamError<I::Item, I::Range>,
    I::Error: ParseError<I::Item, I::Range, X::Position, StreamError = S>,
    I::Error: ParseError<I::Item, I::Range, I::Position, StreamError = S>,  type Item = I::Item; type Range = I::Range; type Position = X::Position; type Error = I::Error;
• impl<S> StreamOnce for Stream<S> where
    S: StreamOnce + Positioned,
    S::Position: Default,  type Item = S::Item; type Range = S::Range; type Position = S::Position; type Error = StreamErrors<S>;
• impl<'a, I> StreamOnce for BufferedStreamRef<'a, I> where
    I: StreamOnce + Positioned + 'a,
    I::Item: Clone + PartialEq + 'a,  type Item = I::Item; type Range = I::Range; type Position = I::Position; type Error = I::Error;