Struct FileConcatReader

pub struct FileConcatReader<I: IntoIterator> { /* private fields */ }

The FileConcatReader struct is a reader over multiple File’s created from an Iterator with AsRef<Path> items.

The reader will only attempt to open and read a file when requested. If the current reader reaches its EOF the FileConcatReader will start reading from the next path in the iterator. If all readers reached EOF the FileConcatReader will also be EOF.

Examples

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

fn main() -> io::Result<()> {
    let files = ["foo.txt", "bar.txt", "baz.txt"];
    let mut c = FileConcatReader::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(())
}

Implementations

impl<I> FileConcatReader<I>

where I: IntoIterator, I::Item: AsRef<Path>,

pub fn new(iter: I) -> Self

Creates a new FileConcatReader from an value which can be converted into an Iterator<Item=AsRef<Path>>.

use std::io::prelude::*;
use concat_reader::*;
fn main() {
    let files = ["foo.txt", "bar.txt", "baz.txt"];
    let mut c = FileConcatReader::new(&files);
}

Trait Implementations

impl<I> ConcatRead for FileConcatReader<I>

where I: IntoIterator, I::Item: AsRef<Path>,

type Item = File

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> Debug for FileConcatReader<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> FileConcatRead for FileConcatReader<I>

where I: IntoIterator, I::Item: AsRef<Path>,

fn file_path(&self) -> Option<&Path>

Returns the path to the current File being read from.

impl<I> From<I> for FileConcatReader<I>

where I: IntoIterator, I::Item: AsRef<Path>,

fn from(iter: I) -> Self

Converts to this type from the input type.

impl<I> Read for FileConcatReader<I>

where I: IntoIterator, I::Item: AsRef<Path>,

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.

fn is_read_vectored(&self) -> bool

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

Determines if this Reader has an efficient read_vectored implementation.

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

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

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

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

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

Reads the exact number of bytes required to fill buf.

fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<(), Error>

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

Pull some bytes from this source into the specified buffer.

fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

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

Reads the exact number of bytes required to fill cursor.

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

where Self: Sized,

Creates a “by reference” adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>

where Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

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

where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another.

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

where Self: Sized,

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