pub struct Ignore {}
Expand description
Ignore all IO requests made on this object.
- For
Write
, that means reporting success always, but not doing anything. - For
Read
andSeek
, that means acting like an immutable empty file.
This may confuse things which use Write
and Seek
together, as writing to an
Ignore
does not advance its seek position, which is not what would happen with a File
or
Cursor
or similar. The Seek
implementation ignores out of bound seeks, negative seeks,
etc., in the hope of maybe mitigating this a bit.
§Example
use iowrap::Ignore;
assert_eq!(0, io::copy(&mut Ignore::new(), &mut Ignore::new()).unwrap());
Implementations§
Trait Implementations§
source§impl BufRead for Ignore
impl BufRead for Ignore
source§fn fill_buf(&mut self) -> Result<&[u8]>
fn fill_buf(&mut self) -> Result<&[u8]>
Returns the contents of the internal buffer, filling it with more data
from the inner reader if it is empty. Read more
source§fn consume(&mut self, _amt: usize)
fn consume(&mut self, _amt: usize)
Tells this buffer that
amt
bytes have been consumed from the buffer,
so they should no longer be returned in calls to read
. Read moresource§fn has_data_left(&mut self) -> Result<bool, Error>
fn has_data_left(&mut self) -> Result<bool, Error>
🔬This is a nightly-only experimental API. (
buf_read_has_data_left
)Check if the underlying
Read
has any data left to be read. Read moresource§fn skip_until(&mut self, byte: u8) -> Result<usize, Error>
fn skip_until(&mut self, byte: u8) -> Result<usize, Error>
🔬This is a nightly-only experimental API. (
bufread_skip_until
)Skip all bytes until the delimiter
byte
or EOF is reached. Read more1.0.0 · source§fn read_line(&mut self, buf: &mut String) -> Result<usize, Error>
fn read_line(&mut self, buf: &mut String) -> Result<usize, Error>
Read all bytes until a newline (the
0xA
byte) is reached, and append
them to the provided String
buffer. Read moresource§impl Read for Ignore
impl Read for Ignore
source§fn read(&mut self, _buf: &mut [u8]) -> Result<usize>
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. Read more
source§fn read_exact(&mut self, buf: &mut [u8]) -> Result<()>
fn read_exact(&mut self, buf: &mut [u8]) -> Result<()>
Read the exact number of bytes required to fill
buf
. Read more1.36.0 · source§fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>
fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>
Like
read
, except that it reads into a slice of buffers. Read moresource§fn is_read_vectored(&self) -> bool
fn is_read_vectored(&self) -> bool
🔬This is a nightly-only experimental API. (
can_vector
)1.0.0 · source§fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>
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
. Read more1.0.0 · source§fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>
fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>
Read all bytes until EOF in this source, appending them to
buf
. Read moresource§fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<(), Error>
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. Read more
source§fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>
fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>
🔬This is a nightly-only experimental API. (
read_buf
)Read the exact number of bytes required to fill
cursor
. Read more1.0.0 · source§fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
Creates a “by reference” adaptor for this instance of
Read
. Read moresource§impl Seek for Ignore
impl Seek for Ignore
source§fn seek(&mut self, _pos: SeekFrom) -> Result<u64>
fn seek(&mut self, _pos: SeekFrom) -> Result<u64>
Seek to an offset, in bytes, in a stream. Read more
1.55.0 · source§fn rewind(&mut self) -> Result<(), Error>
fn rewind(&mut self) -> Result<(), Error>
Rewind to the beginning of a stream. Read more
source§fn stream_len(&mut self) -> Result<u64, Error>
fn stream_len(&mut self) -> Result<u64, Error>
🔬This is a nightly-only experimental API. (
seek_stream_len
)Returns the length of this stream (in bytes). Read more
source§impl Write for Ignore
impl Write for Ignore
source§fn write(&mut self, buf: &[u8]) -> Result<usize>
fn write(&mut self, buf: &[u8]) -> Result<usize>
Write a buffer into this writer, returning how many bytes were written. Read more
source§fn flush(&mut self) -> Result<()>
fn flush(&mut self) -> Result<()>
Flush this output stream, ensuring that all intermediately buffered
contents reach their destination. Read more
source§fn write_all(&mut self, _buf: &[u8]) -> Result<()>
fn write_all(&mut self, _buf: &[u8]) -> Result<()>
Attempts to write an entire buffer into this writer. Read more
source§fn write_fmt(&mut self, _fmt: Arguments<'_>) -> Result<()>
fn write_fmt(&mut self, _fmt: Arguments<'_>) -> Result<()>
Writes a formatted string into this writer, returning any error
encountered. Read more
source§fn is_write_vectored(&self) -> bool
fn is_write_vectored(&self) -> bool
🔬This is a nightly-only experimental API. (
can_vector
)impl Copy for Ignore
Auto Trait Implementations§
impl Freeze for Ignore
impl RefUnwindSafe for Ignore
impl Send for Ignore
impl Sync for Ignore
impl Unpin for Ignore
impl UnwindSafe for Ignore
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<T> CloneToUninit for Twhere
T: Copy,
impl<T> CloneToUninit for Twhere
T: Copy,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
🔬This is a nightly-only experimental API. (
clone_to_uninit
)source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§default unsafe fn clone_to_uninit(&self, dst: *mut T)
default unsafe fn clone_to_uninit(&self, dst: *mut T)
🔬This is a nightly-only experimental API. (
clone_to_uninit
)