Struct Take
#[non_exhaustive]
pub struct Take<T> { pub inner: T, pub len: u64, pub limit: u64 }
Reader adapter which limits the bytes read from an underlying reader.
This struct is generally created by calling take on a reader.
Please see the documentation of take for more details.
Fields
inner: Tlen: u64limit: u64
Implementations
impl<T> Take<T>
fn limit(&self) -> u64Returns the number of bytes that can be read before this instance will return EOF.
Note
This instance may reach
EOFafter reading fewer bytes than indicated by this method if the underlyingReadinstance reaches EOF.Examples
use std::io; use std::io::prelude::*; use std::fs::File; fn main() -> io::Result<()> { let f = File::open("foo.txt")?; // read at most five bytes let handle = f.take(5); println!("limit: {}", handle.limit()); Ok(()) }fn position(&self) -> u64Returns the number of bytes read so far.
fn set_limit(&mut self, limit: u64)Sets the number of bytes that can be read before this instance will return EOF. This is the same as constructing a new
Takeinstance, so the amount of bytes read and the previous limit value don't matter when calling this method.Examples
use std::io; use std::io::prelude::*; use std::fs::File; fn main() -> io::Result<()> { let f = File::open("foo.txt")?; // read at most five bytes let mut handle = f.take(5); handle.set_limit(10); assert_eq!(handle.limit(), 10); Ok(()) }fn into_inner(self) -> TConsumes the
Take, returning the wrapped reader.Examples
use std::io; use std::io::prelude::*; use std::fs::File; fn main() -> io::Result<()> { let mut file = File::open("foo.txt")?; let mut buffer = [0; 5]; let mut handle = file.take(5); handle.read(&mut buffer)?; let file = handle.into_inner(); Ok(()) }fn get_ref(&self) -> &TGets a reference to the underlying reader.
Care should be taken to avoid modifying the internal I/O state of the underlying reader as doing so may corrupt the internal limit of this
Take.Examples
use std::io; use std::io::prelude::*; use std::fs::File; fn main() -> io::Result<()> { let mut file = File::open("foo.txt")?; let mut buffer = [0; 5]; let mut handle = file.take(5); handle.read(&mut buffer)?; let file = handle.get_ref(); Ok(()) }fn get_mut(&mut self) -> &mut TGets a mutable reference to the underlying reader.
Care should be taken to avoid modifying the internal I/O state of the underlying reader as doing so may corrupt the internal limit of this
Take.Examples
use std::io; use std::io::prelude::*; use std::fs::File; fn main() -> io::Result<()> { let mut file = File::open("foo.txt")?; let mut buffer = [0; 5]; let mut handle = file.take(5); handle.read(&mut buffer)?; let file = handle.get_mut(); Ok(()) }
Trait Implementations
impl<T> SizeHint for Take<T>
fn lower_bound(&self) -> usizefn upper_bound(&self) -> Option<usize>
impl<T: Debug> Debug for Take<T>
fn fmt(&self, f: &mut Formatter<'_>) -> Result
impl<T: Seek> Seek for Take<T>
fn seek(&mut self, pos: SeekFrom) -> Result<u64>fn stream_len(&mut self) -> Result<u64>fn stream_position(&mut self) -> Result<u64>fn seek_relative(&mut self, offset: i64) -> Result<()>
Auto Trait Implementations
impl<T> Freeze for Take<T>
where
T: Freeze,
impl<T> RefUnwindSafe for Take<T>
where
T: RefUnwindSafe,
impl<T> Send for Take<T>
where
T: Send,
impl<T> Sync for Take<T>
where
T: Sync,
impl<T> Unpin for Take<T>
where
T: Unpin,
impl<T> UnsafeUnpin for Take<T>
where
T: UnsafeUnpin,
impl<T> UnwindSafe for Take<T>
where
T: UnwindSafe,
Blanket Implementations
impl<T> Any for Take<T>
where
T: 'static + ?Sized,
fn type_id(&self) -> TypeId
impl<T> Borrow<T> for Take<T>
where
T: ?Sized,
fn borrow(&self) -> &T
impl<T> BorrowMut<T> for Take<T>
where
T: ?Sized,
fn borrow_mut(&mut self) -> &mut T
impl<T> From<T> for Take<T>
fn from(t: T) -> TReturns the argument unchanged.
impl<T> SizeHint for Take<T>
where
T: ?Sized,
fn lower_bound(&self) -> usizefn upper_bound(&self) -> Option<usize>
impl<T> SizedTypeProperties for Take<T>
impl<T, U> Into<U> for Take<T>
where
U: From<T>,
fn into(self) -> UCalls
U::from(self).That is, this conversion is whatever the implementation of
[From]<T> for Uchooses to do.
impl<T, U> TryFrom<U> for Take<T>
where
U: Into<T>,
type Error = Infallible;fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>
impl<T, U> TryInto<U> for Take<T>
where
U: TryFrom<T>,
type Error = <U as TryFrom<T>>::Error;fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>