Struct concat_reader::read::ConcatReader

pub struct ConcatReader<I: IntoIterator> { /* fields omitted */ }

The ConcatReader struct allows to read from multiple readers in a sequential order.

If the current reader reaches its EOF the ConcatReader will start reading from the next reader in the iterator. If all readers reached EOF the ConcatReader will also be EOF.

Examples

use concat_reader::*;
use std::fs::File;
use std::io;
use std::io::prelude::*;

fn main() -> io::Result<()> {
    let foo = File::open("foo.txt")?;
    let bar = File::open("bar.txt")?;
    let baz = File::open("bar.txt")?;
    let files = [foo, bar, baz];
    let mut c = ConcatReader::new(&files);
    let mut buffer = [0; 10];

    // read up to 10 bytes
    let n = c.read(&mut buffer[..])?;

    println!("The bytes: {:?}", &buffer[..n]);

    //skip to the next file
    c.skip();

    let mut buffer = Vec::new();
    // read all rest files into a single buffer
    c.read_to_end(&mut buffer)?;
    Ok(())
}

Methods

impl<I> ConcatReader<I> where
    I: IntoIterator,
    I::Item: Read, 

pub fn new(iter: I) -> Self

Creates a new ConcatReader from an value which can be converted into an Iterator<Item=Read>.

use std::io::prelude::*;
use concat_reader::{ConcatRead, ConcatReader};
let bytes = vec!["first".as_bytes(), "second".as_bytes()];
let r = ConcatReader::new(bytes);

Trait Implementations

impl<I> ConcatRead for ConcatReader<I> where
    I: IntoIterator,
    I::Item: Read, 

type Item = I::Item

fn current(&self) -> Option<&Self::Item>

Returns the current Read item in the internal iterator being read from.

fn skip(&mut self) -> bool

Skips to the next [Read] item in the internal [Iterator].

impl<I> From<I> for ConcatReader<I> where
    I: IntoIterator,
    I::Item: Read, 

Important traits for ConcatReader<I>

impl<I> Read for ConcatReader<I> where
    I: IntoIterator,
    I::Item: Read, 

fn from(iter: I) -> ConcatReader<I>

Performs the conversion.

impl<I> Debug for ConcatReader<I> where
    I: IntoIterator,
    I::Item: Debug,
    I::IntoIter: Clone, 

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl<I> Read for ConcatReader<I> where
    I: IntoIterator,
    I::Item: Read, 

fn read(&mut self, buf: &mut [u8]) -> Result<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

unsafe fn initializer(&self) -> Initializer

🔬 This is a nightly-only experimental API. (read_initializer)

Determines if this Reader can work with buffers of uninitialized memory.

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Read all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Read all bytes until EOF in this source, appending them to buf.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Read the exact number of bytes required to fill buf.

fn by_ref(&mut self) -> &mut Self

Creates a "by reference" adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>

Transforms this Read instance to an [Iterator] over its bytes.

fn chain<R>(self, next: R) -> Chain<Self, R> where
    R: Read, 

Creates an adaptor which will chain this stream with another.

fn take(self, limit: u64) -> Take<Self>

Creates an adaptor which will read at most limit bytes from it.